[1] Which of the inert gases can form compounds?
A.
Helium
B.
Xenon
C.
Krypton
D.
Argon
Ans:
Xenon
Explanation :
Xenon compounds are the most numerous of the noble gas compounds that have been formed. Most of them have the xenon atom in the oxidation state of +2, +4, +6, or +8 bonded to highly electronegative atoms such as fluorine or oxygen. Some of these compounds have found use in chemical synthesis as oxidizing agents.
[2] Burning pyrites ore gives out –
A.
Carbon dioxide gas
B.
Sulphur dioxide gas
C.
Nitrogen dioxide gas
D.
Nitric oxide gas
Ans:
Sulphur dioxide gas
Explanation :
The mineral pyrite, or iron pyrite, is an iron sulfide with the formula FeS9. Pyrite remains in commercial use for the production of sulfur dioxide, for use in such applications as the paper industry, and in the manufacture of sulfuric acid.
[3] Milk is -
A.
Emulsion
B.
Suspension
C.
Foam
D.
Gel
Ans:
Emulsion
Explanation :
An emulsion is a mixture of two liquids that cannot combine into a solution. In the case of milk, butterfat globules are suspended in a water-based fluid. The globules are encased in membranes that prevent them from combining into giant lumps of butterfat.
[4] Atomic number of an atom gives the number of which of the following?
A.
electrons
B.
protons
C.
neutrons
D.
neutrons and protons
Ans:
protons
Explanation :
The atomic number or proton number (symbol Z) of a chemical element is the number of protons found in the nucleus of an atom.
[5] Anaemia is caused because of deficiency of which of the following?
A.
Cobalt
B.
Iron
C.
Sodium
D.
Calcium
Ans:
Iron
Explanation :
Anemia is a condition that develops when blood lacks enough healthy red blood cells or hemoglobin. The three main types of anemia are due to blood loss, decreased red blood cell production, and increased red blood cell break down.
[6] Compound having tetrahedral structure is .
A.
C2H4
B.
C2H2
C.
CH4
D.
None of these
Ans:
CH4
Explanation :
Methane is a tetrahedral molecule with four equivalent C-H bonds. Its electronic structure is described by four bonding molecular orbital resulting from the overlap of the valence orbitals on C and H.
[7] Which of the following is produced during the formation of photochemical smog?
A.
Nitrogen Oxides
B.
Hydrocarbons
C.
Methane
D.
Ozone
Ans:
Ozone
Explanation :
Ozone is produced during the formation of photochemical smog. Photochemical smog is a mixture of pollutants that are formed when nitrogen oxides and volatile organic compounds (VOCs) react to sunlight, creating a brown haze above cities.
[8] Benzene cannot undergo –
A.
Substitution
B.
Addition
C.
Elinthaation
D.
Oxidation
Ans:
Elinthaation
Explanation :
Benzene can undergo substitution. Example: Nitration and Suphonation of Benzene. Benzene can undergo addition reaction. Example : Bromo-Benzene Benzene can oxidise to Phenol, Catechol, etc So it do not undergo Elimination reaction. Benzene cannot undergo Elimination reaction.
[9] The polymer obtained by the condensation of hexamethylene diamine and adipic acid is –
A.
Nylon 66
B.
Terylene
C.
Tollen's
D.
Bakelite
Ans:
Nylon 66
Explanation :
Polymers are very high molecular mass substances each molecule of which consists of very large number of simple structural units joined together though covalent bonds in a regular fashion. Polymers whose repeating structural unit are derived from two or more types of monomer units are called copolymers. For examples, in case of nylon 66, the repeating structural unit is derived from two monomer units - hexamethylenediamine and adipic acid.
[10] The antiseptic compound present in dettol is –
A.
Iodine
B.
Enloroxylenol
C.
Biothional
D.
Cresol
Ans:
Enloroxylenol
Explanation :
The active ingredient in Dettol that confers its antiseptic property is chloroxylenol (C8H9ClO), an aromatic chemical compound. Chloroxylenol comprises 4.8% of Dettol's total mixture, with the rest composed of pine oil, isopropanol, castor oil soap, caramel and water.
[11] Amniocentesis is a technique used -
A.
to determine the sex of fetus
B.
to test of amino acid
C.
to test brain
D.
None of the above
Ans:
to determine the sex of fetus
Explanation :
Amniocentesis (also referred to as amniotic fluid test) is a medical procedure used in prenatal diagnosis of chromosomal abnormalities and fetal infections, and also for sex determination.
[12] Bonds formed by the sharing of an electron pair between two atoms are known as -
A.
Covalent bonds
B.
Ionic bonds
C.
Weak bonds
D.
None of the above
Ans:
Covalent bonds
Explanation :
Bonds which are formed by the sharing of an electron pair between two atoms are known as covalent bonds.
[13] The pH of lemon juice is expected to be –
A.
equal to 7
B.
nothing can be predicted
C.
less than 7
D.
more than 7
Ans:
less than 7
Explanation :
The pH level of lemon juice is, 2.00 to 2.60. It varies depending on the lemon. pH expresses different levels of acidity or alkalinity within a solution.
[14] An example of heterocyclic compound is –
A.
Naphthalene
B.
Furan
C.
Benzene
D.
Anthracene
Ans:
Furan
Explanation :
A heterocyclic compound is a cyclic compound that has atoms of at least two different elements as members ails ring (s). Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen.
[15] The pair of compounds used as anesthetic in medicines –
A.
Ether, Ammonia
B.
Nitrous oxide, Chloroform
C.
Chloroform, Nitrogen dioxide
D.
Nitrogen dioxide, ether
Ans:
Nitrous oxide, Chloroform
Explanation :
Nitrous oxide is one of the more well-known anesthetic gases, and has been in use for around 200 years. Unlike some other anesthetics, this compound can be used both for inducing unconsciousness and pain control. Chloroform is more potent and more toxic than ether. Its use as an anaesthetic decreased with increased experience and knowledge of its dangers.
[16] pH scale ranges from –
A.
0 - 7
B.
8 - 14
C.
0 - 14
D.
None
Ans:
0 - 14
Explanation :
The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic. The pH scale is logarithmic and as a result, each whole pH value below 7 is ten times more acidic than the new higher value.
[17] Glass is -
A.
Super cooled liquid
B.
Crystalline solid
C.
Liquid crystal
D.
None of these
Ans:
Super cooled liquid
Explanation :
Glass is sometimes called a Super cooled liquid because it does not form a crystalline structure, but instead forms an amorphous solid that allows molecules in the material to continue to move.
[18] The sum of potential energy and kinetic energy is known as :
A.
Electrical energy
B.
Chemical energy
C.
Light energy
D.
Mechanical energy
Ans:
Mechanical energy
Explanation :
In physical sciences, mechanical energy is the sum ofpotential energy and kinetic energy. It is the energy associated with the motion and position of an object.
[19] Carborundum is another name of –
A.
Silicon carbide
B.
Silicon oxide
C.
Calcium carbide
D.
Calcium oxide
Ans:
Silicon carbide
Explanation :
Silicon carbide, also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass- produced since 1893 for use as an abrasive.
[20] Number of neutrons in an atom of hydrogen is -
A.
One
B.
Zero
C.
Two
D.
Three
Ans:
Zero
Explanation :
Neutrons are the particles in an atom that have a neutral charge. So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. Hydrogen (H) has 1 proton and 1 electron; it does not have any neutron in its nucleus.
[21] Peroxyacetyl nitrate is a –
A.
Acidic dye
B.
Plant hormone
C.
Vitamin
D.
Secondary pollutant
Ans:
Secondary pollutant
Explanation :
Peroxyacetyl nitrate is a secondary pollutant present in photochemical smog (a mixture of air pollutants) that includes both gases and particulates. It is thermally unstable and decomposes into peroxy-ethanoyi radicals and nitrogen dioxide gas. It is a lathIymatory substance.
[22] The term 'brown air' is used for –
A.
Acid fumes
B.
Photochemical smog
C.
Sulphurous smog
D.
Industrial smog
Ans:
Photochemical smog
Explanation :
Photochemical smog which is mainly composed of ozone (O3), Peroxyacetyl nitrate (PAN) and No., is also known as brown air where solar radiation is intense. In seasons of lesser solar radiation or areas, smog formation is incomplete and the air is referred to as grey air.
[23] Soldering of two metals is possible because of the property of –
A.
Viscosity
B.
Osmosis
C.
Cohesion
D.
Surface tension
Ans:
Cohesion
Explanation :
Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting through-out the interior of substance. Soldering leads to alloy formation at the layer between two metals.
[24] An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a –
A.
Power transmittor
B.
Battery
C.
Uninterrupted power supply (UPS)
D.
Generator
Ans:
Uninterrupted power supply (UPS)
Explanation :
A Galvanic cell, also known as battery, is an electro-chemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. It is typically used as a source of electrical power. By their nature, they produce direct current. A battery is a set of galvanic cells that are connected in parallel.
[25] Which method will be employed to test the hardness of water?
A.
Boiling
B.
Distillation
C.
Formation of lather with soap
D.
None of these
Ans:
Formation of lather with soap
Explanation :
Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
Explanation :
Xenon compounds are the most numerous of the noble gas compounds that have been formed. Most of them have the xenon atom in the oxidation state of +2, +4, +6, or +8 bonded to highly electronegative atoms such as fluorine or oxygen. Some of these compounds have found use in chemical synthesis as oxidizing agents.
[2] Burning pyrites ore gives out –
A.
Carbon dioxide gas
B.
Sulphur dioxide gas
C.
Nitrogen dioxide gas
D.
Nitric oxide gas
Ans:
Sulphur dioxide gas
Explanation :
The mineral pyrite, or iron pyrite, is an iron sulfide with the formula FeS9. Pyrite remains in commercial use for the production of sulfur dioxide, for use in such applications as the paper industry, and in the manufacture of sulfuric acid.
[3] Milk is -
A.
Emulsion
B.
Suspension
C.
Foam
D.
Gel
Ans:
Emulsion
Explanation :
An emulsion is a mixture of two liquids that cannot combine into a solution. In the case of milk, butterfat globules are suspended in a water-based fluid. The globules are encased in membranes that prevent them from combining into giant lumps of butterfat.
[4] Atomic number of an atom gives the number of which of the following?
A.
electrons
B.
protons
C.
neutrons
D.
neutrons and protons
Ans:
protons
Explanation :
The atomic number or proton number (symbol Z) of a chemical element is the number of protons found in the nucleus of an atom.
[5] Anaemia is caused because of deficiency of which of the following?
A.
Cobalt
B.
Iron
C.
Sodium
D.
Calcium
Ans:
Iron
Explanation :
Anemia is a condition that develops when blood lacks enough healthy red blood cells or hemoglobin. The three main types of anemia are due to blood loss, decreased red blood cell production, and increased red blood cell break down.
[6] Compound having tetrahedral structure is .
A.
C2H4
B.
C2H2
C.
CH4
D.
None of these
Ans:
CH4
Explanation :
Methane is a tetrahedral molecule with four equivalent C-H bonds. Its electronic structure is described by four bonding molecular orbital resulting from the overlap of the valence orbitals on C and H.
[7] Which of the following is produced during the formation of photochemical smog?
A.
Nitrogen Oxides
B.
Hydrocarbons
C.
Methane
D.
Ozone
Ans:
Ozone
Explanation :
Ozone is produced during the formation of photochemical smog. Photochemical smog is a mixture of pollutants that are formed when nitrogen oxides and volatile organic compounds (VOCs) react to sunlight, creating a brown haze above cities.
[8] Benzene cannot undergo –
A.
Substitution
B.
Addition
C.
Elinthaation
D.
Oxidation
Ans:
Elinthaation
Explanation :
Benzene can undergo substitution. Example: Nitration and Suphonation of Benzene. Benzene can undergo addition reaction. Example : Bromo-Benzene Benzene can oxidise to Phenol, Catechol, etc So it do not undergo Elimination reaction. Benzene cannot undergo Elimination reaction.
[9] The polymer obtained by the condensation of hexamethylene diamine and adipic acid is –
A.
Nylon 66
B.
Terylene
C.
Tollen's
D.
Bakelite
Ans:
Nylon 66
Explanation :
Polymers are very high molecular mass substances each molecule of which consists of very large number of simple structural units joined together though covalent bonds in a regular fashion. Polymers whose repeating structural unit are derived from two or more types of monomer units are called copolymers. For examples, in case of nylon 66, the repeating structural unit is derived from two monomer units - hexamethylenediamine and adipic acid.
[10] The antiseptic compound present in dettol is –
A.
Iodine
B.
Enloroxylenol
C.
Biothional
D.
Cresol
Ans:
Enloroxylenol
Explanation :
The active ingredient in Dettol that confers its antiseptic property is chloroxylenol (C8H9ClO), an aromatic chemical compound. Chloroxylenol comprises 4.8% of Dettol's total mixture, with the rest composed of pine oil, isopropanol, castor oil soap, caramel and water.
[11] Amniocentesis is a technique used -
A.
to determine the sex of fetus
B.
to test of amino acid
C.
to test brain
D.
None of the above
Ans:
to determine the sex of fetus
Explanation :
Amniocentesis (also referred to as amniotic fluid test) is a medical procedure used in prenatal diagnosis of chromosomal abnormalities and fetal infections, and also for sex determination.
[12] Bonds formed by the sharing of an electron pair between two atoms are known as -
A.
Covalent bonds
B.
Ionic bonds
C.
Weak bonds
D.
None of the above
Ans:
Covalent bonds
Explanation :
Bonds which are formed by the sharing of an electron pair between two atoms are known as covalent bonds.
[13] The pH of lemon juice is expected to be –
A.
equal to 7
B.
nothing can be predicted
C.
less than 7
D.
more than 7
Ans:
less than 7
Explanation :
The pH level of lemon juice is, 2.00 to 2.60. It varies depending on the lemon. pH expresses different levels of acidity or alkalinity within a solution.
[14] An example of heterocyclic compound is –
A.
Naphthalene
B.
Furan
C.
Benzene
D.
Anthracene
Ans:
Furan
Explanation :
A heterocyclic compound is a cyclic compound that has atoms of at least two different elements as members ails ring (s). Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen.
[15] The pair of compounds used as anesthetic in medicines –
A.
Ether, Ammonia
B.
Nitrous oxide, Chloroform
C.
Chloroform, Nitrogen dioxide
D.
Nitrogen dioxide, ether
Ans:
Nitrous oxide, Chloroform
Explanation :
Nitrous oxide is one of the more well-known anesthetic gases, and has been in use for around 200 years. Unlike some other anesthetics, this compound can be used both for inducing unconsciousness and pain control. Chloroform is more potent and more toxic than ether. Its use as an anaesthetic decreased with increased experience and knowledge of its dangers.
[16] pH scale ranges from –
A.
0 - 7
B.
8 - 14
C.
0 - 14
D.
None
Ans:
0 - 14
Explanation :
The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic. The pH scale is logarithmic and as a result, each whole pH value below 7 is ten times more acidic than the new higher value.
[17] Glass is -
A.
Super cooled liquid
B.
Crystalline solid
C.
Liquid crystal
D.
None of these
Ans:
Super cooled liquid
Explanation :
Glass is sometimes called a Super cooled liquid because it does not form a crystalline structure, but instead forms an amorphous solid that allows molecules in the material to continue to move.
[18] The sum of potential energy and kinetic energy is known as :
A.
Electrical energy
B.
Chemical energy
C.
Light energy
D.
Mechanical energy
Ans:
Mechanical energy
Explanation :
In physical sciences, mechanical energy is the sum ofpotential energy and kinetic energy. It is the energy associated with the motion and position of an object.
[19] Carborundum is another name of –
A.
Silicon carbide
B.
Silicon oxide
C.
Calcium carbide
D.
Calcium oxide
Ans:
Silicon carbide
Explanation :
Silicon carbide, also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass- produced since 1893 for use as an abrasive.
[20] Number of neutrons in an atom of hydrogen is -
A.
One
B.
Zero
C.
Two
D.
Three
Ans:
Zero
Explanation :
Neutrons are the particles in an atom that have a neutral charge. So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. Hydrogen (H) has 1 proton and 1 electron; it does not have any neutron in its nucleus.
[21] Peroxyacetyl nitrate is a –
A.
Acidic dye
B.
Plant hormone
C.
Vitamin
D.
Secondary pollutant
Ans:
Secondary pollutant
Explanation :
Peroxyacetyl nitrate is a secondary pollutant present in photochemical smog (a mixture of air pollutants) that includes both gases and particulates. It is thermally unstable and decomposes into peroxy-ethanoyi radicals and nitrogen dioxide gas. It is a lathIymatory substance.
[22] The term 'brown air' is used for –
A.
Acid fumes
B.
Photochemical smog
C.
Sulphurous smog
D.
Industrial smog
Ans:
Photochemical smog
Explanation :
Photochemical smog which is mainly composed of ozone (O3), Peroxyacetyl nitrate (PAN) and No., is also known as brown air where solar radiation is intense. In seasons of lesser solar radiation or areas, smog formation is incomplete and the air is referred to as grey air.
[23] Soldering of two metals is possible because of the property of –
A.
Viscosity
B.
Osmosis
C.
Cohesion
D.
Surface tension
Ans:
Cohesion
Explanation :
Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting through-out the interior of substance. Soldering leads to alloy formation at the layer between two metals.
[24] An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a –
A.
Power transmittor
B.
Battery
C.
Uninterrupted power supply (UPS)
D.
Generator
Ans:
Uninterrupted power supply (UPS)
Explanation :
A Galvanic cell, also known as battery, is an electro-chemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. It is typically used as a source of electrical power. By their nature, they produce direct current. A battery is a set of galvanic cells that are connected in parallel.
[25] Which method will be employed to test the hardness of water?
A.
Boiling
B.
Distillation
C.
Formation of lather with soap
D.
None of these
Ans:
Formation of lather with soap
Explanation :
Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
Explanation :
An emulsion is a mixture of two liquids that cannot combine into a solution. In the case of milk, butterfat globules are suspended in a water-based fluid. The globules are encased in membranes that prevent them from combining into giant lumps of butterfat.
[4] Atomic number of an atom gives the number of which of the following?
A.
electrons
B.
protons
C.
neutrons
D.
neutrons and protons
Ans:
protons
Explanation :
The atomic number or proton number (symbol Z) of a chemical element is the number of protons found in the nucleus of an atom.
[5] Anaemia is caused because of deficiency of which of the following?
A.
Cobalt
B.
Iron
C.
Sodium
D.
Calcium
Ans:
Iron
Explanation :
Anemia is a condition that develops when blood lacks enough healthy red blood cells or hemoglobin. The three main types of anemia are due to blood loss, decreased red blood cell production, and increased red blood cell break down.
[6] Compound having tetrahedral structure is .
A.
C2H4
B.
C2H2
C.
CH4
D.
None of these
Ans:
CH4
Explanation :
Methane is a tetrahedral molecule with four equivalent C-H bonds. Its electronic structure is described by four bonding molecular orbital resulting from the overlap of the valence orbitals on C and H.
[7] Which of the following is produced during the formation of photochemical smog?
A.
Nitrogen Oxides
B.
Hydrocarbons
C.
Methane
D.
Ozone
Ans:
Ozone
Explanation :
Ozone is produced during the formation of photochemical smog. Photochemical smog is a mixture of pollutants that are formed when nitrogen oxides and volatile organic compounds (VOCs) react to sunlight, creating a brown haze above cities.
[8] Benzene cannot undergo –
A.
Substitution
B.
Addition
C.
Elinthaation
D.
Oxidation
Ans:
Elinthaation
Explanation :
Benzene can undergo substitution. Example: Nitration and Suphonation of Benzene. Benzene can undergo addition reaction. Example : Bromo-Benzene Benzene can oxidise to Phenol, Catechol, etc So it do not undergo Elimination reaction. Benzene cannot undergo Elimination reaction.
[9] The polymer obtained by the condensation of hexamethylene diamine and adipic acid is –
A.
Nylon 66
B.
Terylene
C.
Tollen's
D.
Bakelite
Ans:
Nylon 66
Explanation :
Polymers are very high molecular mass substances each molecule of which consists of very large number of simple structural units joined together though covalent bonds in a regular fashion. Polymers whose repeating structural unit are derived from two or more types of monomer units are called copolymers. For examples, in case of nylon 66, the repeating structural unit is derived from two monomer units - hexamethylenediamine and adipic acid.
[10] The antiseptic compound present in dettol is –
A.
Iodine
B.
Enloroxylenol
C.
Biothional
D.
Cresol
Ans:
Enloroxylenol
Explanation :
The active ingredient in Dettol that confers its antiseptic property is chloroxylenol (C8H9ClO), an aromatic chemical compound. Chloroxylenol comprises 4.8% of Dettol's total mixture, with the rest composed of pine oil, isopropanol, castor oil soap, caramel and water.
[11] Amniocentesis is a technique used -
A.
to determine the sex of fetus
B.
to test of amino acid
C.
to test brain
D.
None of the above
Ans:
to determine the sex of fetus
Explanation :
Amniocentesis (also referred to as amniotic fluid test) is a medical procedure used in prenatal diagnosis of chromosomal abnormalities and fetal infections, and also for sex determination.
[12] Bonds formed by the sharing of an electron pair between two atoms are known as -
A.
Covalent bonds
B.
Ionic bonds
C.
Weak bonds
D.
None of the above
Ans:
Covalent bonds
Explanation :
Bonds which are formed by the sharing of an electron pair between two atoms are known as covalent bonds.
[13] The pH of lemon juice is expected to be –
A.
equal to 7
B.
nothing can be predicted
C.
less than 7
D.
more than 7
Ans:
less than 7
Explanation :
The pH level of lemon juice is, 2.00 to 2.60. It varies depending on the lemon. pH expresses different levels of acidity or alkalinity within a solution.
[14] An example of heterocyclic compound is –
A.
Naphthalene
B.
Furan
C.
Benzene
D.
Anthracene
Ans:
Furan
Explanation :
A heterocyclic compound is a cyclic compound that has atoms of at least two different elements as members ails ring (s). Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen.
[15] The pair of compounds used as anesthetic in medicines –
A.
Ether, Ammonia
B.
Nitrous oxide, Chloroform
C.
Chloroform, Nitrogen dioxide
D.
Nitrogen dioxide, ether
Ans:
Nitrous oxide, Chloroform
Explanation :
Nitrous oxide is one of the more well-known anesthetic gases, and has been in use for around 200 years. Unlike some other anesthetics, this compound can be used both for inducing unconsciousness and pain control. Chloroform is more potent and more toxic than ether. Its use as an anaesthetic decreased with increased experience and knowledge of its dangers.
[16] pH scale ranges from –
A.
0 - 7
B.
8 - 14
C.
0 - 14
D.
None
Ans:
0 - 14
Explanation :
The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic. The pH scale is logarithmic and as a result, each whole pH value below 7 is ten times more acidic than the new higher value.
[17] Glass is -
A.
Super cooled liquid
B.
Crystalline solid
C.
Liquid crystal
D.
None of these
Ans:
Super cooled liquid
Explanation :
Glass is sometimes called a Super cooled liquid because it does not form a crystalline structure, but instead forms an amorphous solid that allows molecules in the material to continue to move.
[18] The sum of potential energy and kinetic energy is known as :
A.
Electrical energy
B.
Chemical energy
C.
Light energy
D.
Mechanical energy
Ans:
Mechanical energy
Explanation :
In physical sciences, mechanical energy is the sum ofpotential energy and kinetic energy. It is the energy associated with the motion and position of an object.
[19] Carborundum is another name of –
A.
Silicon carbide
B.
Silicon oxide
C.
Calcium carbide
D.
Calcium oxide
Ans:
Silicon carbide
Explanation :
Silicon carbide, also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass- produced since 1893 for use as an abrasive.
[20] Number of neutrons in an atom of hydrogen is -
A.
One
B.
Zero
C.
Two
D.
Three
Ans:
Zero
Explanation :
Neutrons are the particles in an atom that have a neutral charge. So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. Hydrogen (H) has 1 proton and 1 electron; it does not have any neutron in its nucleus.
[21] Peroxyacetyl nitrate is a –
A.
Acidic dye
B.
Plant hormone
C.
Vitamin
D.
Secondary pollutant
Ans:
Secondary pollutant
Explanation :
Peroxyacetyl nitrate is a secondary pollutant present in photochemical smog (a mixture of air pollutants) that includes both gases and particulates. It is thermally unstable and decomposes into peroxy-ethanoyi radicals and nitrogen dioxide gas. It is a lathIymatory substance.
[22] The term 'brown air' is used for –
A.
Acid fumes
B.
Photochemical smog
C.
Sulphurous smog
D.
Industrial smog
Ans:
Photochemical smog
Explanation :
Photochemical smog which is mainly composed of ozone (O3), Peroxyacetyl nitrate (PAN) and No., is also known as brown air where solar radiation is intense. In seasons of lesser solar radiation or areas, smog formation is incomplete and the air is referred to as grey air.
[23] Soldering of two metals is possible because of the property of –
A.
Viscosity
B.
Osmosis
C.
Cohesion
D.
Surface tension
Ans:
Cohesion
Explanation :
Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting through-out the interior of substance. Soldering leads to alloy formation at the layer between two metals.
[24] An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a –
A.
Power transmittor
B.
Battery
C.
Uninterrupted power supply (UPS)
D.
Generator
Ans:
Uninterrupted power supply (UPS)
Explanation :
A Galvanic cell, also known as battery, is an electro-chemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. It is typically used as a source of electrical power. By their nature, they produce direct current. A battery is a set of galvanic cells that are connected in parallel.
[25] Which method will be employed to test the hardness of water?
A.
Boiling
B.
Distillation
C.
Formation of lather with soap
D.
None of these
Ans:
Formation of lather with soap
Explanation :
Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
Explanation :
Anemia is a condition that develops when blood lacks enough healthy red blood cells or hemoglobin. The three main types of anemia are due to blood loss, decreased red blood cell production, and increased red blood cell break down.
[6] Compound having tetrahedral structure is .
A.
C2H4
B.
C2H2
C.
CH4
D.
None of these
Ans:
CH4
Explanation :
Methane is a tetrahedral molecule with four equivalent C-H bonds. Its electronic structure is described by four bonding molecular orbital resulting from the overlap of the valence orbitals on C and H.
[7] Which of the following is produced during the formation of photochemical smog?
A.
Nitrogen Oxides
B.
Hydrocarbons
C.
Methane
D.
Ozone
Ans:
Ozone
Explanation :
Ozone is produced during the formation of photochemical smog. Photochemical smog is a mixture of pollutants that are formed when nitrogen oxides and volatile organic compounds (VOCs) react to sunlight, creating a brown haze above cities.
[8] Benzene cannot undergo –
A.
Substitution
B.
Addition
C.
Elinthaation
D.
Oxidation
Ans:
Elinthaation
Explanation :
Benzene can undergo substitution. Example: Nitration and Suphonation of Benzene. Benzene can undergo addition reaction. Example : Bromo-Benzene Benzene can oxidise to Phenol, Catechol, etc So it do not undergo Elimination reaction. Benzene cannot undergo Elimination reaction.
[9] The polymer obtained by the condensation of hexamethylene diamine and adipic acid is –
A.
Nylon 66
B.
Terylene
C.
Tollen's
D.
Bakelite
Ans:
Nylon 66
Explanation :
Polymers are very high molecular mass substances each molecule of which consists of very large number of simple structural units joined together though covalent bonds in a regular fashion. Polymers whose repeating structural unit are derived from two or more types of monomer units are called copolymers. For examples, in case of nylon 66, the repeating structural unit is derived from two monomer units - hexamethylenediamine and adipic acid.
[10] The antiseptic compound present in dettol is –
A.
Iodine
B.
Enloroxylenol
C.
Biothional
D.
Cresol
Ans:
Enloroxylenol
Explanation :
The active ingredient in Dettol that confers its antiseptic property is chloroxylenol (C8H9ClO), an aromatic chemical compound. Chloroxylenol comprises 4.8% of Dettol's total mixture, with the rest composed of pine oil, isopropanol, castor oil soap, caramel and water.
[11] Amniocentesis is a technique used -
A.
to determine the sex of fetus
B.
to test of amino acid
C.
to test brain
D.
None of the above
Ans:
to determine the sex of fetus
Explanation :
Amniocentesis (also referred to as amniotic fluid test) is a medical procedure used in prenatal diagnosis of chromosomal abnormalities and fetal infections, and also for sex determination.
[12] Bonds formed by the sharing of an electron pair between two atoms are known as -
A.
Covalent bonds
B.
Ionic bonds
C.
Weak bonds
D.
None of the above
Ans:
Covalent bonds
Explanation :
Bonds which are formed by the sharing of an electron pair between two atoms are known as covalent bonds.
[13] The pH of lemon juice is expected to be –
A.
equal to 7
B.
nothing can be predicted
C.
less than 7
D.
more than 7
Ans:
less than 7
Explanation :
The pH level of lemon juice is, 2.00 to 2.60. It varies depending on the lemon. pH expresses different levels of acidity or alkalinity within a solution.
[14] An example of heterocyclic compound is –
A.
Naphthalene
B.
Furan
C.
Benzene
D.
Anthracene
Ans:
Furan
Explanation :
A heterocyclic compound is a cyclic compound that has atoms of at least two different elements as members ails ring (s). Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen.
[15] The pair of compounds used as anesthetic in medicines –
A.
Ether, Ammonia
B.
Nitrous oxide, Chloroform
C.
Chloroform, Nitrogen dioxide
D.
Nitrogen dioxide, ether
Ans:
Nitrous oxide, Chloroform
Explanation :
Nitrous oxide is one of the more well-known anesthetic gases, and has been in use for around 200 years. Unlike some other anesthetics, this compound can be used both for inducing unconsciousness and pain control. Chloroform is more potent and more toxic than ether. Its use as an anaesthetic decreased with increased experience and knowledge of its dangers.
[16] pH scale ranges from –
A.
0 - 7
B.
8 - 14
C.
0 - 14
D.
None
Ans:
0 - 14
Explanation :
The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic. The pH scale is logarithmic and as a result, each whole pH value below 7 is ten times more acidic than the new higher value.
[17] Glass is -
A.
Super cooled liquid
B.
Crystalline solid
C.
Liquid crystal
D.
None of these
Ans:
Super cooled liquid
Explanation :
Glass is sometimes called a Super cooled liquid because it does not form a crystalline structure, but instead forms an amorphous solid that allows molecules in the material to continue to move.
[18] The sum of potential energy and kinetic energy is known as :
A.
Electrical energy
B.
Chemical energy
C.
Light energy
D.
Mechanical energy
Ans:
Mechanical energy
Explanation :
In physical sciences, mechanical energy is the sum ofpotential energy and kinetic energy. It is the energy associated with the motion and position of an object.
[19] Carborundum is another name of –
A.
Silicon carbide
B.
Silicon oxide
C.
Calcium carbide
D.
Calcium oxide
Ans:
Silicon carbide
Explanation :
Silicon carbide, also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass- produced since 1893 for use as an abrasive.
[20] Number of neutrons in an atom of hydrogen is -
A.
One
B.
Zero
C.
Two
D.
Three
Ans:
Zero
Explanation :
Neutrons are the particles in an atom that have a neutral charge. So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. Hydrogen (H) has 1 proton and 1 electron; it does not have any neutron in its nucleus.
[21] Peroxyacetyl nitrate is a –
A.
Acidic dye
B.
Plant hormone
C.
Vitamin
D.
Secondary pollutant
Ans:
Secondary pollutant
Explanation :
Peroxyacetyl nitrate is a secondary pollutant present in photochemical smog (a mixture of air pollutants) that includes both gases and particulates. It is thermally unstable and decomposes into peroxy-ethanoyi radicals and nitrogen dioxide gas. It is a lathIymatory substance.
[22] The term 'brown air' is used for –
A.
Acid fumes
B.
Photochemical smog
C.
Sulphurous smog
D.
Industrial smog
Ans:
Photochemical smog
Explanation :
Photochemical smog which is mainly composed of ozone (O3), Peroxyacetyl nitrate (PAN) and No., is also known as brown air where solar radiation is intense. In seasons of lesser solar radiation or areas, smog formation is incomplete and the air is referred to as grey air.
[23] Soldering of two metals is possible because of the property of –
A.
Viscosity
B.
Osmosis
C.
Cohesion
D.
Surface tension
Ans:
Cohesion
Explanation :
Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting through-out the interior of substance. Soldering leads to alloy formation at the layer between two metals.
[24] An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a –
A.
Power transmittor
B.
Battery
C.
Uninterrupted power supply (UPS)
D.
Generator
Ans:
Uninterrupted power supply (UPS)
Explanation :
A Galvanic cell, also known as battery, is an electro-chemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. It is typically used as a source of electrical power. By their nature, they produce direct current. A battery is a set of galvanic cells that are connected in parallel.
[25] Which method will be employed to test the hardness of water?
A.
Boiling
B.
Distillation
C.
Formation of lather with soap
D.
None of these
Ans:
Formation of lather with soap
Explanation :
Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
Explanation :
Ozone is produced during the formation of photochemical smog. Photochemical smog is a mixture of pollutants that are formed when nitrogen oxides and volatile organic compounds (VOCs) react to sunlight, creating a brown haze above cities.
[8] Benzene cannot undergo –
A.
Substitution
B.
Addition
C.
Elinthaation
D.
Oxidation
Ans:
Elinthaation
Explanation :
Benzene can undergo substitution. Example: Nitration and Suphonation of Benzene. Benzene can undergo addition reaction. Example : Bromo-Benzene Benzene can oxidise to Phenol, Catechol, etc So it do not undergo Elimination reaction. Benzene cannot undergo Elimination reaction.
[9] The polymer obtained by the condensation of hexamethylene diamine and adipic acid is –
A.
Nylon 66
B.
Terylene
C.
Tollen's
D.
Bakelite
Ans:
Nylon 66
Explanation :
Polymers are very high molecular mass substances each molecule of which consists of very large number of simple structural units joined together though covalent bonds in a regular fashion. Polymers whose repeating structural unit are derived from two or more types of monomer units are called copolymers. For examples, in case of nylon 66, the repeating structural unit is derived from two monomer units - hexamethylenediamine and adipic acid.
[10] The antiseptic compound present in dettol is –
A.
Iodine
B.
Enloroxylenol
C.
Biothional
D.
Cresol
Ans:
Enloroxylenol
Explanation :
The active ingredient in Dettol that confers its antiseptic property is chloroxylenol (C8H9ClO), an aromatic chemical compound. Chloroxylenol comprises 4.8% of Dettol's total mixture, with the rest composed of pine oil, isopropanol, castor oil soap, caramel and water.
[11] Amniocentesis is a technique used -
A.
to determine the sex of fetus
B.
to test of amino acid
C.
to test brain
D.
None of the above
Ans:
to determine the sex of fetus
Explanation :
Amniocentesis (also referred to as amniotic fluid test) is a medical procedure used in prenatal diagnosis of chromosomal abnormalities and fetal infections, and also for sex determination.
[12] Bonds formed by the sharing of an electron pair between two atoms are known as -
A.
Covalent bonds
B.
Ionic bonds
C.
Weak bonds
D.
None of the above
Ans:
Covalent bonds
Explanation :
Bonds which are formed by the sharing of an electron pair between two atoms are known as covalent bonds.
[13] The pH of lemon juice is expected to be –
A.
equal to 7
B.
nothing can be predicted
C.
less than 7
D.
more than 7
Ans:
less than 7
Explanation :
The pH level of lemon juice is, 2.00 to 2.60. It varies depending on the lemon. pH expresses different levels of acidity or alkalinity within a solution.
[14] An example of heterocyclic compound is –
A.
Naphthalene
B.
Furan
C.
Benzene
D.
Anthracene
Ans:
Furan
Explanation :
A heterocyclic compound is a cyclic compound that has atoms of at least two different elements as members ails ring (s). Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen.
[15] The pair of compounds used as anesthetic in medicines –
A.
Ether, Ammonia
B.
Nitrous oxide, Chloroform
C.
Chloroform, Nitrogen dioxide
D.
Nitrogen dioxide, ether
Ans:
Nitrous oxide, Chloroform
Explanation :
Nitrous oxide is one of the more well-known anesthetic gases, and has been in use for around 200 years. Unlike some other anesthetics, this compound can be used both for inducing unconsciousness and pain control. Chloroform is more potent and more toxic than ether. Its use as an anaesthetic decreased with increased experience and knowledge of its dangers.
[16] pH scale ranges from –
A.
0 - 7
B.
8 - 14
C.
0 - 14
D.
None
Ans:
0 - 14
Explanation :
The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic. The pH scale is logarithmic and as a result, each whole pH value below 7 is ten times more acidic than the new higher value.
[17] Glass is -
A.
Super cooled liquid
B.
Crystalline solid
C.
Liquid crystal
D.
None of these
Ans:
Super cooled liquid
Explanation :
Glass is sometimes called a Super cooled liquid because it does not form a crystalline structure, but instead forms an amorphous solid that allows molecules in the material to continue to move.
[18] The sum of potential energy and kinetic energy is known as :
A.
Electrical energy
B.
Chemical energy
C.
Light energy
D.
Mechanical energy
Ans:
Mechanical energy
Explanation :
In physical sciences, mechanical energy is the sum ofpotential energy and kinetic energy. It is the energy associated with the motion and position of an object.
[19] Carborundum is another name of –
A.
Silicon carbide
B.
Silicon oxide
C.
Calcium carbide
D.
Calcium oxide
Ans:
Silicon carbide
Explanation :
Silicon carbide, also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass- produced since 1893 for use as an abrasive.
[20] Number of neutrons in an atom of hydrogen is -
A.
One
B.
Zero
C.
Two
D.
Three
Ans:
Zero
Explanation :
Neutrons are the particles in an atom that have a neutral charge. So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. Hydrogen (H) has 1 proton and 1 electron; it does not have any neutron in its nucleus.
[21] Peroxyacetyl nitrate is a –
A.
Acidic dye
B.
Plant hormone
C.
Vitamin
D.
Secondary pollutant
Ans:
Secondary pollutant
Explanation :
Peroxyacetyl nitrate is a secondary pollutant present in photochemical smog (a mixture of air pollutants) that includes both gases and particulates. It is thermally unstable and decomposes into peroxy-ethanoyi radicals and nitrogen dioxide gas. It is a lathIymatory substance.
[22] The term 'brown air' is used for –
A.
Acid fumes
B.
Photochemical smog
C.
Sulphurous smog
D.
Industrial smog
Ans:
Photochemical smog
Explanation :
Photochemical smog which is mainly composed of ozone (O3), Peroxyacetyl nitrate (PAN) and No., is also known as brown air where solar radiation is intense. In seasons of lesser solar radiation or areas, smog formation is incomplete and the air is referred to as grey air.
[23] Soldering of two metals is possible because of the property of –
A.
Viscosity
B.
Osmosis
C.
Cohesion
D.
Surface tension
Ans:
Cohesion
Explanation :
Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting through-out the interior of substance. Soldering leads to alloy formation at the layer between two metals.
[24] An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a –
A.
Power transmittor
B.
Battery
C.
Uninterrupted power supply (UPS)
D.
Generator
Ans:
Uninterrupted power supply (UPS)
Explanation :
A Galvanic cell, also known as battery, is an electro-chemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. It is typically used as a source of electrical power. By their nature, they produce direct current. A battery is a set of galvanic cells that are connected in parallel.
[25] Which method will be employed to test the hardness of water?
A.
Boiling
B.
Distillation
C.
Formation of lather with soap
D.
None of these
Ans:
Formation of lather with soap
Explanation :
Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
Explanation :
Polymers are very high molecular mass substances each molecule of which consists of very large number of simple structural units joined together though covalent bonds in a regular fashion. Polymers whose repeating structural unit are derived from two or more types of monomer units are called copolymers. For examples, in case of nylon 66, the repeating structural unit is derived from two monomer units - hexamethylenediamine and adipic acid.
[10] The antiseptic compound present in dettol is –
A.
Iodine
B.
Enloroxylenol
C.
Biothional
D.
Cresol
Ans:
Enloroxylenol
Explanation :
The active ingredient in Dettol that confers its antiseptic property is chloroxylenol (C8H9ClO), an aromatic chemical compound. Chloroxylenol comprises 4.8% of Dettol's total mixture, with the rest composed of pine oil, isopropanol, castor oil soap, caramel and water.
[11] Amniocentesis is a technique used -
A.
to determine the sex of fetus
B.
to test of amino acid
C.
to test brain
D.
None of the above
Ans:
to determine the sex of fetus
Explanation :
Amniocentesis (also referred to as amniotic fluid test) is a medical procedure used in prenatal diagnosis of chromosomal abnormalities and fetal infections, and also for sex determination.
[12] Bonds formed by the sharing of an electron pair between two atoms are known as -
A.
Covalent bonds
B.
Ionic bonds
C.
Weak bonds
D.
None of the above
Ans:
Covalent bonds
Explanation :
Bonds which are formed by the sharing of an electron pair between two atoms are known as covalent bonds.
[13] The pH of lemon juice is expected to be –
A.
equal to 7
B.
nothing can be predicted
C.
less than 7
D.
more than 7
Ans:
less than 7
Explanation :
The pH level of lemon juice is, 2.00 to 2.60. It varies depending on the lemon. pH expresses different levels of acidity or alkalinity within a solution.
[14] An example of heterocyclic compound is –
A.
Naphthalene
B.
Furan
C.
Benzene
D.
Anthracene
Ans:
Furan
Explanation :
A heterocyclic compound is a cyclic compound that has atoms of at least two different elements as members ails ring (s). Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen.
[15] The pair of compounds used as anesthetic in medicines –
A.
Ether, Ammonia
B.
Nitrous oxide, Chloroform
C.
Chloroform, Nitrogen dioxide
D.
Nitrogen dioxide, ether
Ans:
Nitrous oxide, Chloroform
Explanation :
Nitrous oxide is one of the more well-known anesthetic gases, and has been in use for around 200 years. Unlike some other anesthetics, this compound can be used both for inducing unconsciousness and pain control. Chloroform is more potent and more toxic than ether. Its use as an anaesthetic decreased with increased experience and knowledge of its dangers.
[16] pH scale ranges from –
A.
0 - 7
B.
8 - 14
C.
0 - 14
D.
None
Ans:
0 - 14
Explanation :
The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic. The pH scale is logarithmic and as a result, each whole pH value below 7 is ten times more acidic than the new higher value.
[17] Glass is -
A.
Super cooled liquid
B.
Crystalline solid
C.
Liquid crystal
D.
None of these
Ans:
Super cooled liquid
Explanation :
Glass is sometimes called a Super cooled liquid because it does not form a crystalline structure, but instead forms an amorphous solid that allows molecules in the material to continue to move.
[18] The sum of potential energy and kinetic energy is known as :
A.
Electrical energy
B.
Chemical energy
C.
Light energy
D.
Mechanical energy
Ans:
Mechanical energy
Explanation :
In physical sciences, mechanical energy is the sum ofpotential energy and kinetic energy. It is the energy associated with the motion and position of an object.
[19] Carborundum is another name of –
A.
Silicon carbide
B.
Silicon oxide
C.
Calcium carbide
D.
Calcium oxide
Ans:
Silicon carbide
Explanation :
Silicon carbide, also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass- produced since 1893 for use as an abrasive.
[20] Number of neutrons in an atom of hydrogen is -
A.
One
B.
Zero
C.
Two
D.
Three
Ans:
Zero
Explanation :
Neutrons are the particles in an atom that have a neutral charge. So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. Hydrogen (H) has 1 proton and 1 electron; it does not have any neutron in its nucleus.
[21] Peroxyacetyl nitrate is a –
A.
Acidic dye
B.
Plant hormone
C.
Vitamin
D.
Secondary pollutant
Ans:
Secondary pollutant
Explanation :
Peroxyacetyl nitrate is a secondary pollutant present in photochemical smog (a mixture of air pollutants) that includes both gases and particulates. It is thermally unstable and decomposes into peroxy-ethanoyi radicals and nitrogen dioxide gas. It is a lathIymatory substance.
[22] The term 'brown air' is used for –
A.
Acid fumes
B.
Photochemical smog
C.
Sulphurous smog
D.
Industrial smog
Ans:
Photochemical smog
Explanation :
Photochemical smog which is mainly composed of ozone (O3), Peroxyacetyl nitrate (PAN) and No., is also known as brown air where solar radiation is intense. In seasons of lesser solar radiation or areas, smog formation is incomplete and the air is referred to as grey air.
[23] Soldering of two metals is possible because of the property of –
A.
Viscosity
B.
Osmosis
C.
Cohesion
D.
Surface tension
Ans:
Cohesion
Explanation :
Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting through-out the interior of substance. Soldering leads to alloy formation at the layer between two metals.
[24] An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a –
A.
Power transmittor
B.
Battery
C.
Uninterrupted power supply (UPS)
D.
Generator
Ans:
Uninterrupted power supply (UPS)
Explanation :
A Galvanic cell, also known as battery, is an electro-chemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. It is typically used as a source of electrical power. By their nature, they produce direct current. A battery is a set of galvanic cells that are connected in parallel.
[25] Which method will be employed to test the hardness of water?
A.
Boiling
B.
Distillation
C.
Formation of lather with soap
D.
None of these
Ans:
Formation of lather with soap
Explanation :
Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
Explanation :
Amniocentesis (also referred to as amniotic fluid test) is a medical procedure used in prenatal diagnosis of chromosomal abnormalities and fetal infections, and also for sex determination.
[12] Bonds formed by the sharing of an electron pair between two atoms are known as -
A.
Covalent bonds
B.
Ionic bonds
C.
Weak bonds
D.
None of the above
Ans:
Covalent bonds
Explanation :
Bonds which are formed by the sharing of an electron pair between two atoms are known as covalent bonds.
[13] The pH of lemon juice is expected to be –
A.
equal to 7
B.
nothing can be predicted
C.
less than 7
D.
more than 7
Ans:
less than 7
Explanation :
The pH level of lemon juice is, 2.00 to 2.60. It varies depending on the lemon. pH expresses different levels of acidity or alkalinity within a solution.
[14] An example of heterocyclic compound is –
A.
Naphthalene
B.
Furan
C.
Benzene
D.
Anthracene
Ans:
Furan
Explanation :
A heterocyclic compound is a cyclic compound that has atoms of at least two different elements as members ails ring (s). Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen.
[15] The pair of compounds used as anesthetic in medicines –
A.
Ether, Ammonia
B.
Nitrous oxide, Chloroform
C.
Chloroform, Nitrogen dioxide
D.
Nitrogen dioxide, ether
Ans:
Nitrous oxide, Chloroform
Explanation :
Nitrous oxide is one of the more well-known anesthetic gases, and has been in use for around 200 years. Unlike some other anesthetics, this compound can be used both for inducing unconsciousness and pain control. Chloroform is more potent and more toxic than ether. Its use as an anaesthetic decreased with increased experience and knowledge of its dangers.
[16] pH scale ranges from –
A.
0 - 7
B.
8 - 14
C.
0 - 14
D.
None
Ans:
0 - 14
Explanation :
The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic. The pH scale is logarithmic and as a result, each whole pH value below 7 is ten times more acidic than the new higher value.
[17] Glass is -
A.
Super cooled liquid
B.
Crystalline solid
C.
Liquid crystal
D.
None of these
Ans:
Super cooled liquid
Explanation :
Glass is sometimes called a Super cooled liquid because it does not form a crystalline structure, but instead forms an amorphous solid that allows molecules in the material to continue to move.
[18] The sum of potential energy and kinetic energy is known as :
A.
Electrical energy
B.
Chemical energy
C.
Light energy
D.
Mechanical energy
Ans:
Mechanical energy
Explanation :
In physical sciences, mechanical energy is the sum ofpotential energy and kinetic energy. It is the energy associated with the motion and position of an object.
[19] Carborundum is another name of –
A.
Silicon carbide
B.
Silicon oxide
C.
Calcium carbide
D.
Calcium oxide
Ans:
Silicon carbide
Explanation :
Silicon carbide, also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass- produced since 1893 for use as an abrasive.
[20] Number of neutrons in an atom of hydrogen is -
A.
One
B.
Zero
C.
Two
D.
Three
Ans:
Zero
Explanation :
Neutrons are the particles in an atom that have a neutral charge. So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. Hydrogen (H) has 1 proton and 1 electron; it does not have any neutron in its nucleus.
[21] Peroxyacetyl nitrate is a –
A.
Acidic dye
B.
Plant hormone
C.
Vitamin
D.
Secondary pollutant
Ans:
Secondary pollutant
Explanation :
Peroxyacetyl nitrate is a secondary pollutant present in photochemical smog (a mixture of air pollutants) that includes both gases and particulates. It is thermally unstable and decomposes into peroxy-ethanoyi radicals and nitrogen dioxide gas. It is a lathIymatory substance.
[22] The term 'brown air' is used for –
A.
Acid fumes
B.
Photochemical smog
C.
Sulphurous smog
D.
Industrial smog
Ans:
Photochemical smog
Explanation :
Photochemical smog which is mainly composed of ozone (O3), Peroxyacetyl nitrate (PAN) and No., is also known as brown air where solar radiation is intense. In seasons of lesser solar radiation or areas, smog formation is incomplete and the air is referred to as grey air.
[23] Soldering of two metals is possible because of the property of –
A.
Viscosity
B.
Osmosis
C.
Cohesion
D.
Surface tension
Ans:
Cohesion
Explanation :
Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting through-out the interior of substance. Soldering leads to alloy formation at the layer between two metals.
[24] An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a –
A.
Power transmittor
B.
Battery
C.
Uninterrupted power supply (UPS)
D.
Generator
Ans:
Uninterrupted power supply (UPS)
Explanation :
A Galvanic cell, also known as battery, is an electro-chemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. It is typically used as a source of electrical power. By their nature, they produce direct current. A battery is a set of galvanic cells that are connected in parallel.
[25] Which method will be employed to test the hardness of water?
A.
Boiling
B.
Distillation
C.
Formation of lather with soap
D.
None of these
Ans:
Formation of lather with soap
Explanation :
Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
Explanation :
The pH level of lemon juice is, 2.00 to 2.60. It varies depending on the lemon. pH expresses different levels of acidity or alkalinity within a solution.
[14] An example of heterocyclic compound is –
A.
Naphthalene
B.
Furan
C.
Benzene
D.
Anthracene
Ans:
Furan
Explanation :
A heterocyclic compound is a cyclic compound that has atoms of at least two different elements as members ails ring (s). Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen.
[15] The pair of compounds used as anesthetic in medicines –
A.
Ether, Ammonia
B.
Nitrous oxide, Chloroform
C.
Chloroform, Nitrogen dioxide
D.
Nitrogen dioxide, ether
Ans:
Nitrous oxide, Chloroform
Explanation :
Nitrous oxide is one of the more well-known anesthetic gases, and has been in use for around 200 years. Unlike some other anesthetics, this compound can be used both for inducing unconsciousness and pain control. Chloroform is more potent and more toxic than ether. Its use as an anaesthetic decreased with increased experience and knowledge of its dangers.
[16] pH scale ranges from –
A.
0 - 7
B.
8 - 14
C.
0 - 14
D.
None
Ans:
0 - 14
Explanation :
The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic. The pH scale is logarithmic and as a result, each whole pH value below 7 is ten times more acidic than the new higher value.
[17] Glass is -
A.
Super cooled liquid
B.
Crystalline solid
C.
Liquid crystal
D.
None of these
Ans:
Super cooled liquid
Explanation :
Glass is sometimes called a Super cooled liquid because it does not form a crystalline structure, but instead forms an amorphous solid that allows molecules in the material to continue to move.
[18] The sum of potential energy and kinetic energy is known as :
A.
Electrical energy
B.
Chemical energy
C.
Light energy
D.
Mechanical energy
Ans:
Mechanical energy
Explanation :
In physical sciences, mechanical energy is the sum ofpotential energy and kinetic energy. It is the energy associated with the motion and position of an object.
[19] Carborundum is another name of –
A.
Silicon carbide
B.
Silicon oxide
C.
Calcium carbide
D.
Calcium oxide
Ans:
Silicon carbide
Explanation :
Silicon carbide, also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass- produced since 1893 for use as an abrasive.
[20] Number of neutrons in an atom of hydrogen is -
A.
One
B.
Zero
C.
Two
D.
Three
Ans:
Zero
Explanation :
Neutrons are the particles in an atom that have a neutral charge. So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. Hydrogen (H) has 1 proton and 1 electron; it does not have any neutron in its nucleus.
[21] Peroxyacetyl nitrate is a –
A.
Acidic dye
B.
Plant hormone
C.
Vitamin
D.
Secondary pollutant
Ans:
Secondary pollutant
Explanation :
Peroxyacetyl nitrate is a secondary pollutant present in photochemical smog (a mixture of air pollutants) that includes both gases and particulates. It is thermally unstable and decomposes into peroxy-ethanoyi radicals and nitrogen dioxide gas. It is a lathIymatory substance.
[22] The term 'brown air' is used for –
A.
Acid fumes
B.
Photochemical smog
C.
Sulphurous smog
D.
Industrial smog
Ans:
Photochemical smog
Explanation :
Photochemical smog which is mainly composed of ozone (O3), Peroxyacetyl nitrate (PAN) and No., is also known as brown air where solar radiation is intense. In seasons of lesser solar radiation or areas, smog formation is incomplete and the air is referred to as grey air.
[23] Soldering of two metals is possible because of the property of –
A.
Viscosity
B.
Osmosis
C.
Cohesion
D.
Surface tension
Ans:
Cohesion
Explanation :
Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting through-out the interior of substance. Soldering leads to alloy formation at the layer between two metals.
[24] An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a –
A.
Power transmittor
B.
Battery
C.
Uninterrupted power supply (UPS)
D.
Generator
Ans:
Uninterrupted power supply (UPS)
Explanation :
A Galvanic cell, also known as battery, is an electro-chemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. It is typically used as a source of electrical power. By their nature, they produce direct current. A battery is a set of galvanic cells that are connected in parallel.
[25] Which method will be employed to test the hardness of water?
A.
Boiling
B.
Distillation
C.
Formation of lather with soap
D.
None of these
Ans:
Formation of lather with soap
Explanation :
Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
Explanation :
Nitrous oxide is one of the more well-known anesthetic gases, and has been in use for around 200 years. Unlike some other anesthetics, this compound can be used both for inducing unconsciousness and pain control. Chloroform is more potent and more toxic than ether. Its use as an anaesthetic decreased with increased experience and knowledge of its dangers.
[16] pH scale ranges from –
A.
0 - 7
B.
8 - 14
C.
0 - 14
D.
None
Ans:
0 - 14
Explanation :
The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic. The pH scale is logarithmic and as a result, each whole pH value below 7 is ten times more acidic than the new higher value.
[17] Glass is -
A.
Super cooled liquid
B.
Crystalline solid
C.
Liquid crystal
D.
None of these
Ans:
Super cooled liquid
Explanation :
Glass is sometimes called a Super cooled liquid because it does not form a crystalline structure, but instead forms an amorphous solid that allows molecules in the material to continue to move.
[18] The sum of potential energy and kinetic energy is known as :
A.
Electrical energy
B.
Chemical energy
C.
Light energy
D.
Mechanical energy
Ans:
Mechanical energy
Explanation :
In physical sciences, mechanical energy is the sum ofpotential energy and kinetic energy. It is the energy associated with the motion and position of an object.
[19] Carborundum is another name of –
A.
Silicon carbide
B.
Silicon oxide
C.
Calcium carbide
D.
Calcium oxide
Ans:
Silicon carbide
Explanation :
Silicon carbide, also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass- produced since 1893 for use as an abrasive.
[20] Number of neutrons in an atom of hydrogen is -
A.
One
B.
Zero
C.
Two
D.
Three
Ans:
Zero
Explanation :
Neutrons are the particles in an atom that have a neutral charge. So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. Hydrogen (H) has 1 proton and 1 electron; it does not have any neutron in its nucleus.
[21] Peroxyacetyl nitrate is a –
A.
Acidic dye
B.
Plant hormone
C.
Vitamin
D.
Secondary pollutant
Ans:
Secondary pollutant
Explanation :
Peroxyacetyl nitrate is a secondary pollutant present in photochemical smog (a mixture of air pollutants) that includes both gases and particulates. It is thermally unstable and decomposes into peroxy-ethanoyi radicals and nitrogen dioxide gas. It is a lathIymatory substance.
[22] The term 'brown air' is used for –
A.
Acid fumes
B.
Photochemical smog
C.
Sulphurous smog
D.
Industrial smog
Ans:
Photochemical smog
Explanation :
Photochemical smog which is mainly composed of ozone (O3), Peroxyacetyl nitrate (PAN) and No., is also known as brown air where solar radiation is intense. In seasons of lesser solar radiation or areas, smog formation is incomplete and the air is referred to as grey air.
[23] Soldering of two metals is possible because of the property of –
A.
Viscosity
B.
Osmosis
C.
Cohesion
D.
Surface tension
Ans:
Cohesion
Explanation :
Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting through-out the interior of substance. Soldering leads to alloy formation at the layer between two metals.
[24] An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a –
A.
Power transmittor
B.
Battery
C.
Uninterrupted power supply (UPS)
D.
Generator
Ans:
Uninterrupted power supply (UPS)
Explanation :
A Galvanic cell, also known as battery, is an electro-chemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. It is typically used as a source of electrical power. By their nature, they produce direct current. A battery is a set of galvanic cells that are connected in parallel.
[25] Which method will be employed to test the hardness of water?
A.
Boiling
B.
Distillation
C.
Formation of lather with soap
D.
None of these
Ans:
Formation of lather with soap
Explanation :
Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
Explanation :
Glass is sometimes called a Super cooled liquid because it does not form a crystalline structure, but instead forms an amorphous solid that allows molecules in the material to continue to move.
[18] The sum of potential energy and kinetic energy is known as :
A.
Electrical energy
B.
Chemical energy
C.
Light energy
D.
Mechanical energy
Ans:
Mechanical energy
Explanation :
In physical sciences, mechanical energy is the sum ofpotential energy and kinetic energy. It is the energy associated with the motion and position of an object.
[19] Carborundum is another name of –
A.
Silicon carbide
B.
Silicon oxide
C.
Calcium carbide
D.
Calcium oxide
Ans:
Silicon carbide
Explanation :
Silicon carbide, also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass- produced since 1893 for use as an abrasive.
[20] Number of neutrons in an atom of hydrogen is -
A.
One
B.
Zero
C.
Two
D.
Three
Ans:
Zero
Explanation :
Neutrons are the particles in an atom that have a neutral charge. So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. Hydrogen (H) has 1 proton and 1 electron; it does not have any neutron in its nucleus.
[21] Peroxyacetyl nitrate is a –
A.
Acidic dye
B.
Plant hormone
C.
Vitamin
D.
Secondary pollutant
Ans:
Secondary pollutant
Explanation :
Peroxyacetyl nitrate is a secondary pollutant present in photochemical smog (a mixture of air pollutants) that includes both gases and particulates. It is thermally unstable and decomposes into peroxy-ethanoyi radicals and nitrogen dioxide gas. It is a lathIymatory substance.
[22] The term 'brown air' is used for –
A.
Acid fumes
B.
Photochemical smog
C.
Sulphurous smog
D.
Industrial smog
Ans:
Photochemical smog
Explanation :
Photochemical smog which is mainly composed of ozone (O3), Peroxyacetyl nitrate (PAN) and No., is also known as brown air where solar radiation is intense. In seasons of lesser solar radiation or areas, smog formation is incomplete and the air is referred to as grey air.
[23] Soldering of two metals is possible because of the property of –
A.
Viscosity
B.
Osmosis
C.
Cohesion
D.
Surface tension
Ans:
Cohesion
Explanation :
Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting through-out the interior of substance. Soldering leads to alloy formation at the layer between two metals.
[24] An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a –
A.
Power transmittor
B.
Battery
C.
Uninterrupted power supply (UPS)
D.
Generator
Ans:
Uninterrupted power supply (UPS)
Explanation :
A Galvanic cell, also known as battery, is an electro-chemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. It is typically used as a source of electrical power. By their nature, they produce direct current. A battery is a set of galvanic cells that are connected in parallel.
[25] Which method will be employed to test the hardness of water?
A.
Boiling
B.
Distillation
C.
Formation of lather with soap
D.
None of these
Ans:
Formation of lather with soap
Explanation :
Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
Explanation :
Silicon carbide, also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass- produced since 1893 for use as an abrasive.
[20] Number of neutrons in an atom of hydrogen is -
A.
One
B.
Zero
C.
Two
D.
Three
Ans:
Zero
Explanation :
Neutrons are the particles in an atom that have a neutral charge. So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. Hydrogen (H) has 1 proton and 1 electron; it does not have any neutron in its nucleus.
[21] Peroxyacetyl nitrate is a –
A.
Acidic dye
B.
Plant hormone
C.
Vitamin
D.
Secondary pollutant
Ans:
Secondary pollutant
Explanation :
Peroxyacetyl nitrate is a secondary pollutant present in photochemical smog (a mixture of air pollutants) that includes both gases and particulates. It is thermally unstable and decomposes into peroxy-ethanoyi radicals and nitrogen dioxide gas. It is a lathIymatory substance.
[22] The term 'brown air' is used for –
A.
Acid fumes
B.
Photochemical smog
C.
Sulphurous smog
D.
Industrial smog
Ans:
Photochemical smog
Explanation :
Photochemical smog which is mainly composed of ozone (O3), Peroxyacetyl nitrate (PAN) and No., is also known as brown air where solar radiation is intense. In seasons of lesser solar radiation or areas, smog formation is incomplete and the air is referred to as grey air.
[23] Soldering of two metals is possible because of the property of –
A.
Viscosity
B.
Osmosis
C.
Cohesion
D.
Surface tension
Ans:
Cohesion
Explanation :
Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting through-out the interior of substance. Soldering leads to alloy formation at the layer between two metals.
[24] An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a –
A.
Power transmittor
B.
Battery
C.
Uninterrupted power supply (UPS)
D.
Generator
Ans:
Uninterrupted power supply (UPS)
Explanation :
A Galvanic cell, also known as battery, is an electro-chemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. It is typically used as a source of electrical power. By their nature, they produce direct current. A battery is a set of galvanic cells that are connected in parallel.
[25] Which method will be employed to test the hardness of water?
A.
Boiling
B.
Distillation
C.
Formation of lather with soap
D.
None of these
Ans:
Formation of lather with soap
Explanation :
Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
Explanation :
Peroxyacetyl nitrate is a secondary pollutant present in photochemical smog (a mixture of air pollutants) that includes both gases and particulates. It is thermally unstable and decomposes into peroxy-ethanoyi radicals and nitrogen dioxide gas. It is a lathIymatory substance.
[22] The term 'brown air' is used for –
A.
Acid fumes
B.
Photochemical smog
C.
Sulphurous smog
D.
Industrial smog
Ans:
Photochemical smog
Explanation :
Photochemical smog which is mainly composed of ozone (O3), Peroxyacetyl nitrate (PAN) and No., is also known as brown air where solar radiation is intense. In seasons of lesser solar radiation or areas, smog formation is incomplete and the air is referred to as grey air.
[23] Soldering of two metals is possible because of the property of –
A.
Viscosity
B.
Osmosis
C.
Cohesion
D.
Surface tension
Ans:
Cohesion
Explanation :
Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting through-out the interior of substance. Soldering leads to alloy formation at the layer between two metals.
[24] An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a –
A.
Power transmittor
B.
Battery
C.
Uninterrupted power supply (UPS)
D.
Generator
Ans:
Uninterrupted power supply (UPS)
Explanation :
A Galvanic cell, also known as battery, is an electro-chemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. It is typically used as a source of electrical power. By their nature, they produce direct current. A battery is a set of galvanic cells that are connected in parallel.
[25] Which method will be employed to test the hardness of water?
A.
Boiling
B.
Distillation
C.
Formation of lather with soap
D.
None of these
Ans:
Formation of lather with soap
Explanation :
Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
Explanation :
Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting through-out the interior of substance. Soldering leads to alloy formation at the layer between two metals.
[24] An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a –
A.
Power transmittor
B.
Battery
C.
Uninterrupted power supply (UPS)
D.
Generator
Ans:
Uninterrupted power supply (UPS)
Explanation :
A Galvanic cell, also known as battery, is an electro-chemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. It is typically used as a source of electrical power. By their nature, they produce direct current. A battery is a set of galvanic cells that are connected in parallel.
[25] Which method will be employed to test the hardness of water?
A.
Boiling
B.
Distillation
C.
Formation of lather with soap
D.
None of these
Ans:
Formation of lather with soap
Explanation :
Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
Explanation :
Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.