[1] Permanent - hardness of water may be removed by addition of –
A.
Alum
B.
Sodium carbonate
C.
Lime
D.
Potassium Permangante
Ans:
Sodium carbonate
Explanation :
Sodium carbonate (also known as washing soda or soda ash) is a sodium salt of carbonic acid. In domestic use, it is used as a water softener in laundering. It competes with the magnesium and calcium ions in hard water and prevents them from bonding with the detergent being used. Sodium carbonate can be used to remove grease, oil and wine stains.
[2] Which of the following is the best fuel in terms of energy released per gram of fuel?
A.
Hydrogen
B.
Methane
C.
Ethanol
D.
Butane
Ans:
Hydrogen
Explanation :
The amount of energy released increases with the number of bonds present in the chemical substance or fuel. That is because each bond has a certain amount of energy stored in it therefore the more bonds the more energy is stored and more energy is released if these bonds break through combustion. Theoretical values of energy released per gram of fuel (in joules/ gram) are: Hydrogen: 142.5 KJ/g; Methane: 55.6 KJ/ g; Ethanol: 29.7 KJ /g; Butane: 49.6KJ/g.
[3] One carat of diamond is equal to -
A.
100mg
B.
150mg
C.
200mg
D.
250mg
Ans:
200mg
Explanation :
One carat is equal to 200 milligrams, or in other words, a 5-carat stone weighs 1 gram. The weight of one carat is precisely 0.2 grams.
[4] The manufacture of iron from iron ore involves the process of –
A.
oxidation
B.
reduction
C.
fractional distillation
D.
electrolysis
Ans:
reduction
Explanation :
The manufacture of iron ore involves the process of reduction. Important ores of iron : Haematite, Magnetite.
[5] Which of the following is caused by the higher concentration of Nitrogen and Phosphorous?
A.
Eutrophication
B.
Hardness
C.
Alkalinity
D.
Acidity
Ans:
Eutrophication
Explanation :
Higher concentration of Nitrogen and Phosphorus causes Eutrophication.
[6] The smallest particle of an element is called -
A.
Ion
B.
Electron
C.
Atom
D.
Molecule
Ans:
Atom
Explanation :
An element is a substance completely made up of one atom. However, the atom itself is not the smallest known particle, but instead each atom is made up of three individual parts: electrons, protons and neutrons.
[7] There are some substances whose odor changes in acidic or basic media. These are called -
A.
Olfactory indicators
B.
Litmus indicator
C.
Gustatory indicators
D.
All of the above
Ans:
Olfactory indicators
Explanation :
An Olfactory indicator is a substance whose smell varies depending on whether it is mixed with an acidic or basic solution. Onion , clove oil and vanilla extract are examples.
[8] Which of the following elements has the atomic number greater than that of Phosphorus?
A.
Aluminium
B.
Silicon
C.
Chlorine
D.
Magnesium
Ans:
Chlorine
Explanation :
Chlorine is a chemical element with symbol Cl and atomic number 17. Phosphorus is a chemical element with symbol P and atomic number 15.
[9] If the sewage is fully oxidized, the nitrogen is in the form of –
A.
Nitrites
B.
Ammonia
C.
Nitramines
D.
Nitrates
Ans:
Nitrates
Explanation :
Oxidized forms of nitrogen include nitrite (NO2) and nitrate (NO3). Nitrogen mainly occurs in wastewater in this form. Because nitrite is easily oxidized to nitrate, nitrate is the compound predominantly found in groundwater and surface waters.
[10] Which among the following is used to dilute oxygen in the gas cylinders used by divers?
A.
Krypton
B.
Argon
C.
Helium
D.
Neon
Ans:
Helium
Explanation :
Helium is used to dilute the oxygen and nitrogen to reduce these affects. Helium is the gas of choice to use because it is an inert gas, is thinner, therefore more compressible than air, and its narcotic properties are negligible in comparison to nitrogen.
[11] Which one of the following does not form oxyacid?
A.
Sulphur
B.
Chlorine
C.
Nitrogen
D.
Fluorine
Ans:
Fluorine
Explanation :
Fluorine cannot form oxyacid because fluorine is more electronegative than oxygen. For oxygen to bind, it must be a positively charged ion.
[12] The gas used to extinguish fire is –
A.
Neon
B.
Nitrogen
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon monoxide
Explanation :
Fires require these 3 things: a fuel (a hydrocarbon, which is a compound containing only carbon and hydrogen), a source of oxygen, and heal. Carbon Dioxide is most commonly used to extinguish fire as it displaces wwgen, thus choking the very source of a fire.
[13] _is not an allotrope of carbon.
A.
Buckminsterfullerene
B.
Carbon Doxide
C.
Diamond
D.
Graphite
Ans:
Carbon Doxide
Explanation :
Carbon is capable of forming many allotropes due to its valency. Well-known forms of carbon include diamond and graphite. Other allotropes in clude: include buckyballs (fullerenes), amorphous carbon, glassy carbon, carbon nanofoam, nanotubes,and others.
[14] Which hydrocarbons are the major constituents of 'LPG'?
A.
Methane and Ethane
B.
Propane and Butane
C.
Pentane and Benzene
D.
Only Methane
Ans:
Propane and Butane
Explanation :
Cooking gas, also known as Liquefied Petroleum Gas (LPG) is primarily propane (C3Hg) and butane (C4H10).
[15] When cathode rays strike a target of high atomic weight, they give rise to –
A.
α -rays
B.
β and γ rays
C.
X-rays
D.
positive rays
Ans:
X-rays
Explanation :
When cathode rays strike a solid target of high atomic weight and high melting point such as tungsten, molybdenum, etc, they give rise to a highly pen-etrating radiation called the X-rays (LIT Physics by Dr. P.K Aganval).
[16] The major use of sulphur is in the manufacture of –
A.
H2SO4
B.
H2S
C.
SO2
D.
Fungicide
Ans:
H2SO4
Explanation :
The major use of sulphur is in the manufacture of sulphuric acid (H2SO4) which is one of the most important compounds made by the chemical industry. It is used to make, literally, hundreds of compounds needed by almost every industry.
[17] Which of the following will replace hydrogen from acids to form salts?
A.
S
B.
Na
C.
Ag
D.
P
Ans:
Na
Explanation :
All acids contain hydrogen atom (s). Dilute acids react with some metals such as Sodium, Potassium, Calcium, iron, etc to form salts. Sodium replaces two hydrogen atoms from Sulfuric acid (H2SO4) to form a normal salt, Sodium Sulphate (Na2SO4).
[18] Which of the following metals has least, melting point?
A.
Gold
B.
Silver
C.
Mercury
D.
Copper
Ans:
Mercury
Explanation :
The melting point of the given metals (in Celsius) are:- Gold: 1063; Silver: 961; Copper: 1083; Mercury: - 38.86. Mercury is the only elemental metal known to melt at a generally cold temperature.
[19] Water gas is the combination of –
A.
CO and H2
B.
CO2 and H2
C.
CO and H2O
D.
CO2 and CO
Ans:
CO and H2
Explanation :
Water has is a synthesis gas, containing carbon monoxide (CO) and hydrogen has (H2). It is made by passing steam over a red-hot carbon fuel such as coke. The reaction between steam and hydrocarbons produce the has mixture.
[20] Which of the following elements is obtained from sea weeds?
A.
Iodine
B.
Vanadium
C.
Argon
D.
Sulphur
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and anti-okidants, which help strengthen immunity.
[21] If there is one million Mg2+ ions in MgCl2, how many chloride ions are there?
A.
Two million
B.
One million
C.
Half a million
D.
Ten million
Ans:
Two million
Explanation :
Using formula of Stoichiometry, 1mol MgCl2 : 1mol Mg2+: 2mol Cl-. There are two moles of chloride ions for every one mole of MgCl2. So if there is one million Mg2+ ions in MgCl2, there will be two million chloride ions in it
[22] The gas that causes suffocation and death when coal or coke is burnt in a closed room is -
A.
Methane
B.
Ethane
C.
Carbon monoxide
D.
Carbon dioxide
Ans:
Carbon monoxide
Explanation :
Exhaust fumes of motor cars, gases produced, from coal fire in a closed room and coal gas, all contain carbon monoxide, which is the cause of their poisonous nature. When carbon monoxide is inhaled, it prevents the oxygen from combining with hemoglobin and instead combines itself with hemoglobin to form carboxyhaemoglobin, which is stable compound. This causes oxygen starvation in the body tissues and eventually causes death by suffocation.
[23] the correct formula for ammonium phosphate.
A.
N4H6PO4
B.
(NH4)3PO
C.
(NH4)3PO4
D.
(NH4)2PO4
Ans:
(NH4)3PO4
Explanation :
(NH4)3PO4 is a the chemical formula for ammonium phosphate. For more chemistry related queries log on to website world of chemicals.
[24] Teryleneisa condensation polymer of ethylene glycol and which acid?
A.
Benzoic Acid
B.
Salicylic acid
C.
Phthalic acid
D.
Terephthalic acid
Ans:
Terephthalic acid
Explanation :
Terylene is a co-polymer of ethylene glycol and Terephthalic acid. Also known as Dacron, it is prepared by the condensation polymerization of ethylene glycerol and. Terephthalic acid with elimination of water. The reaction is carried out at about 420-460 K in the presence of a catalyst consisting of a mixture of zinc acetate and antimony trioxide.
[25] Which of the following ores does not contain iron?
A.
Haematite
B.
Magnetite
C.
Limonite
D.
Cassiterite
Ans:
Cassiterite
Explanation :
Haematite is Fe2O3, magnetite is Fe3O4 and Magnesite is MgCO3. ∴ Magnesite is not ore of iron.
Explanation :
Sodium carbonate (also known as washing soda or soda ash) is a sodium salt of carbonic acid. In domestic use, it is used as a water softener in laundering. It competes with the magnesium and calcium ions in hard water and prevents them from bonding with the detergent being used. Sodium carbonate can be used to remove grease, oil and wine stains.
[2] Which of the following is the best fuel in terms of energy released per gram of fuel?
A.
Hydrogen
B.
Methane
C.
Ethanol
D.
Butane
Ans:
Hydrogen
Explanation :
The amount of energy released increases with the number of bonds present in the chemical substance or fuel. That is because each bond has a certain amount of energy stored in it therefore the more bonds the more energy is stored and more energy is released if these bonds break through combustion. Theoretical values of energy released per gram of fuel (in joules/ gram) are: Hydrogen: 142.5 KJ/g; Methane: 55.6 KJ/ g; Ethanol: 29.7 KJ /g; Butane: 49.6KJ/g.
[3] One carat of diamond is equal to -
A.
100mg
B.
150mg
C.
200mg
D.
250mg
Ans:
200mg
Explanation :
One carat is equal to 200 milligrams, or in other words, a 5-carat stone weighs 1 gram. The weight of one carat is precisely 0.2 grams.
[4] The manufacture of iron from iron ore involves the process of –
A.
oxidation
B.
reduction
C.
fractional distillation
D.
electrolysis
Ans:
reduction
Explanation :
The manufacture of iron ore involves the process of reduction. Important ores of iron : Haematite, Magnetite.
[5] Which of the following is caused by the higher concentration of Nitrogen and Phosphorous?
A.
Eutrophication
B.
Hardness
C.
Alkalinity
D.
Acidity
Ans:
Eutrophication
Explanation :
Higher concentration of Nitrogen and Phosphorus causes Eutrophication.
[6] The smallest particle of an element is called -
A.
Ion
B.
Electron
C.
Atom
D.
Molecule
Ans:
Atom
Explanation :
An element is a substance completely made up of one atom. However, the atom itself is not the smallest known particle, but instead each atom is made up of three individual parts: electrons, protons and neutrons.
[7] There are some substances whose odor changes in acidic or basic media. These are called -
A.
Olfactory indicators
B.
Litmus indicator
C.
Gustatory indicators
D.
All of the above
Ans:
Olfactory indicators
Explanation :
An Olfactory indicator is a substance whose smell varies depending on whether it is mixed with an acidic or basic solution. Onion , clove oil and vanilla extract are examples.
[8] Which of the following elements has the atomic number greater than that of Phosphorus?
A.
Aluminium
B.
Silicon
C.
Chlorine
D.
Magnesium
Ans:
Chlorine
Explanation :
Chlorine is a chemical element with symbol Cl and atomic number 17. Phosphorus is a chemical element with symbol P and atomic number 15.
[9] If the sewage is fully oxidized, the nitrogen is in the form of –
A.
Nitrites
B.
Ammonia
C.
Nitramines
D.
Nitrates
Ans:
Nitrates
Explanation :
Oxidized forms of nitrogen include nitrite (NO2) and nitrate (NO3). Nitrogen mainly occurs in wastewater in this form. Because nitrite is easily oxidized to nitrate, nitrate is the compound predominantly found in groundwater and surface waters.
[10] Which among the following is used to dilute oxygen in the gas cylinders used by divers?
A.
Krypton
B.
Argon
C.
Helium
D.
Neon
Ans:
Helium
Explanation :
Helium is used to dilute the oxygen and nitrogen to reduce these affects. Helium is the gas of choice to use because it is an inert gas, is thinner, therefore more compressible than air, and its narcotic properties are negligible in comparison to nitrogen.
[11] Which one of the following does not form oxyacid?
A.
Sulphur
B.
Chlorine
C.
Nitrogen
D.
Fluorine
Ans:
Fluorine
Explanation :
Fluorine cannot form oxyacid because fluorine is more electronegative than oxygen. For oxygen to bind, it must be a positively charged ion.
[12] The gas used to extinguish fire is –
A.
Neon
B.
Nitrogen
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon monoxide
Explanation :
Fires require these 3 things: a fuel (a hydrocarbon, which is a compound containing only carbon and hydrogen), a source of oxygen, and heal. Carbon Dioxide is most commonly used to extinguish fire as it displaces wwgen, thus choking the very source of a fire.
[13] _is not an allotrope of carbon.
A.
Buckminsterfullerene
B.
Carbon Doxide
C.
Diamond
D.
Graphite
Ans:
Carbon Doxide
Explanation :
Carbon is capable of forming many allotropes due to its valency. Well-known forms of carbon include diamond and graphite. Other allotropes in clude: include buckyballs (fullerenes), amorphous carbon, glassy carbon, carbon nanofoam, nanotubes,and others.
[14] Which hydrocarbons are the major constituents of 'LPG'?
A.
Methane and Ethane
B.
Propane and Butane
C.
Pentane and Benzene
D.
Only Methane
Ans:
Propane and Butane
Explanation :
Cooking gas, also known as Liquefied Petroleum Gas (LPG) is primarily propane (C3Hg) and butane (C4H10).
[15] When cathode rays strike a target of high atomic weight, they give rise to –
A.
α -rays
B.
β and γ rays
C.
X-rays
D.
positive rays
Ans:
X-rays
Explanation :
When cathode rays strike a solid target of high atomic weight and high melting point such as tungsten, molybdenum, etc, they give rise to a highly pen-etrating radiation called the X-rays (LIT Physics by Dr. P.K Aganval).
[16] The major use of sulphur is in the manufacture of –
A.
H2SO4
B.
H2S
C.
SO2
D.
Fungicide
Ans:
H2SO4
Explanation :
The major use of sulphur is in the manufacture of sulphuric acid (H2SO4) which is one of the most important compounds made by the chemical industry. It is used to make, literally, hundreds of compounds needed by almost every industry.
[17] Which of the following will replace hydrogen from acids to form salts?
A.
S
B.
Na
C.
Ag
D.
P
Ans:
Na
Explanation :
All acids contain hydrogen atom (s). Dilute acids react with some metals such as Sodium, Potassium, Calcium, iron, etc to form salts. Sodium replaces two hydrogen atoms from Sulfuric acid (H2SO4) to form a normal salt, Sodium Sulphate (Na2SO4).
[18] Which of the following metals has least, melting point?
A.
Gold
B.
Silver
C.
Mercury
D.
Copper
Ans:
Mercury
Explanation :
The melting point of the given metals (in Celsius) are:- Gold: 1063; Silver: 961; Copper: 1083; Mercury: - 38.86. Mercury is the only elemental metal known to melt at a generally cold temperature.
[19] Water gas is the combination of –
A.
CO and H2
B.
CO2 and H2
C.
CO and H2O
D.
CO2 and CO
Ans:
CO and H2
Explanation :
Water has is a synthesis gas, containing carbon monoxide (CO) and hydrogen has (H2). It is made by passing steam over a red-hot carbon fuel such as coke. The reaction between steam and hydrocarbons produce the has mixture.
[20] Which of the following elements is obtained from sea weeds?
A.
Iodine
B.
Vanadium
C.
Argon
D.
Sulphur
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and anti-okidants, which help strengthen immunity.
[21] If there is one million Mg2+ ions in MgCl2, how many chloride ions are there?
A.
Two million
B.
One million
C.
Half a million
D.
Ten million
Ans:
Two million
Explanation :
Using formula of Stoichiometry, 1mol MgCl2 : 1mol Mg2+: 2mol Cl-. There are two moles of chloride ions for every one mole of MgCl2. So if there is one million Mg2+ ions in MgCl2, there will be two million chloride ions in it
[22] The gas that causes suffocation and death when coal or coke is burnt in a closed room is -
A.
Methane
B.
Ethane
C.
Carbon monoxide
D.
Carbon dioxide
Ans:
Carbon monoxide
Explanation :
Exhaust fumes of motor cars, gases produced, from coal fire in a closed room and coal gas, all contain carbon monoxide, which is the cause of their poisonous nature. When carbon monoxide is inhaled, it prevents the oxygen from combining with hemoglobin and instead combines itself with hemoglobin to form carboxyhaemoglobin, which is stable compound. This causes oxygen starvation in the body tissues and eventually causes death by suffocation.
[23] the correct formula for ammonium phosphate.
A.
N4H6PO4
B.
(NH4)3PO
C.
(NH4)3PO4
D.
(NH4)2PO4
Ans:
(NH4)3PO4
Explanation :
(NH4)3PO4 is a the chemical formula for ammonium phosphate. For more chemistry related queries log on to website world of chemicals.
[24] Teryleneisa condensation polymer of ethylene glycol and which acid?
A.
Benzoic Acid
B.
Salicylic acid
C.
Phthalic acid
D.
Terephthalic acid
Ans:
Terephthalic acid
Explanation :
Terylene is a co-polymer of ethylene glycol and Terephthalic acid. Also known as Dacron, it is prepared by the condensation polymerization of ethylene glycerol and. Terephthalic acid with elimination of water. The reaction is carried out at about 420-460 K in the presence of a catalyst consisting of a mixture of zinc acetate and antimony trioxide.
[25] Which of the following ores does not contain iron?
A.
Haematite
B.
Magnetite
C.
Limonite
D.
Cassiterite
Ans:
Cassiterite
Explanation :
Haematite is Fe2O3, magnetite is Fe3O4 and Magnesite is MgCO3. ∴ Magnesite is not ore of iron.
Explanation :
One carat is equal to 200 milligrams, or in other words, a 5-carat stone weighs 1 gram. The weight of one carat is precisely 0.2 grams.
[4] The manufacture of iron from iron ore involves the process of –
A.
oxidation
B.
reduction
C.
fractional distillation
D.
electrolysis
Ans:
reduction
Explanation :
The manufacture of iron ore involves the process of reduction. Important ores of iron : Haematite, Magnetite.
[5] Which of the following is caused by the higher concentration of Nitrogen and Phosphorous?
A.
Eutrophication
B.
Hardness
C.
Alkalinity
D.
Acidity
Ans:
Eutrophication
Explanation :
Higher concentration of Nitrogen and Phosphorus causes Eutrophication.
[6] The smallest particle of an element is called -
A.
Ion
B.
Electron
C.
Atom
D.
Molecule
Ans:
Atom
Explanation :
An element is a substance completely made up of one atom. However, the atom itself is not the smallest known particle, but instead each atom is made up of three individual parts: electrons, protons and neutrons.
[7] There are some substances whose odor changes in acidic or basic media. These are called -
A.
Olfactory indicators
B.
Litmus indicator
C.
Gustatory indicators
D.
All of the above
Ans:
Olfactory indicators
Explanation :
An Olfactory indicator is a substance whose smell varies depending on whether it is mixed with an acidic or basic solution. Onion , clove oil and vanilla extract are examples.
[8] Which of the following elements has the atomic number greater than that of Phosphorus?
A.
Aluminium
B.
Silicon
C.
Chlorine
D.
Magnesium
Ans:
Chlorine
Explanation :
Chlorine is a chemical element with symbol Cl and atomic number 17. Phosphorus is a chemical element with symbol P and atomic number 15.
[9] If the sewage is fully oxidized, the nitrogen is in the form of –
A.
Nitrites
B.
Ammonia
C.
Nitramines
D.
Nitrates
Ans:
Nitrates
Explanation :
Oxidized forms of nitrogen include nitrite (NO2) and nitrate (NO3). Nitrogen mainly occurs in wastewater in this form. Because nitrite is easily oxidized to nitrate, nitrate is the compound predominantly found in groundwater and surface waters.
[10] Which among the following is used to dilute oxygen in the gas cylinders used by divers?
A.
Krypton
B.
Argon
C.
Helium
D.
Neon
Ans:
Helium
Explanation :
Helium is used to dilute the oxygen and nitrogen to reduce these affects. Helium is the gas of choice to use because it is an inert gas, is thinner, therefore more compressible than air, and its narcotic properties are negligible in comparison to nitrogen.
[11] Which one of the following does not form oxyacid?
A.
Sulphur
B.
Chlorine
C.
Nitrogen
D.
Fluorine
Ans:
Fluorine
Explanation :
Fluorine cannot form oxyacid because fluorine is more electronegative than oxygen. For oxygen to bind, it must be a positively charged ion.
[12] The gas used to extinguish fire is –
A.
Neon
B.
Nitrogen
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon monoxide
Explanation :
Fires require these 3 things: a fuel (a hydrocarbon, which is a compound containing only carbon and hydrogen), a source of oxygen, and heal. Carbon Dioxide is most commonly used to extinguish fire as it displaces wwgen, thus choking the very source of a fire.
[13] _is not an allotrope of carbon.
A.
Buckminsterfullerene
B.
Carbon Doxide
C.
Diamond
D.
Graphite
Ans:
Carbon Doxide
Explanation :
Carbon is capable of forming many allotropes due to its valency. Well-known forms of carbon include diamond and graphite. Other allotropes in clude: include buckyballs (fullerenes), amorphous carbon, glassy carbon, carbon nanofoam, nanotubes,and others.
[14] Which hydrocarbons are the major constituents of 'LPG'?
A.
Methane and Ethane
B.
Propane and Butane
C.
Pentane and Benzene
D.
Only Methane
Ans:
Propane and Butane
Explanation :
Cooking gas, also known as Liquefied Petroleum Gas (LPG) is primarily propane (C3Hg) and butane (C4H10).
[15] When cathode rays strike a target of high atomic weight, they give rise to –
A.
α -rays
B.
β and γ rays
C.
X-rays
D.
positive rays
Ans:
X-rays
Explanation :
When cathode rays strike a solid target of high atomic weight and high melting point such as tungsten, molybdenum, etc, they give rise to a highly pen-etrating radiation called the X-rays (LIT Physics by Dr. P.K Aganval).
[16] The major use of sulphur is in the manufacture of –
A.
H2SO4
B.
H2S
C.
SO2
D.
Fungicide
Ans:
H2SO4
Explanation :
The major use of sulphur is in the manufacture of sulphuric acid (H2SO4) which is one of the most important compounds made by the chemical industry. It is used to make, literally, hundreds of compounds needed by almost every industry.
[17] Which of the following will replace hydrogen from acids to form salts?
A.
S
B.
Na
C.
Ag
D.
P
Ans:
Na
Explanation :
All acids contain hydrogen atom (s). Dilute acids react with some metals such as Sodium, Potassium, Calcium, iron, etc to form salts. Sodium replaces two hydrogen atoms from Sulfuric acid (H2SO4) to form a normal salt, Sodium Sulphate (Na2SO4).
[18] Which of the following metals has least, melting point?
A.
Gold
B.
Silver
C.
Mercury
D.
Copper
Ans:
Mercury
Explanation :
The melting point of the given metals (in Celsius) are:- Gold: 1063; Silver: 961; Copper: 1083; Mercury: - 38.86. Mercury is the only elemental metal known to melt at a generally cold temperature.
[19] Water gas is the combination of –
A.
CO and H2
B.
CO2 and H2
C.
CO and H2O
D.
CO2 and CO
Ans:
CO and H2
Explanation :
Water has is a synthesis gas, containing carbon monoxide (CO) and hydrogen has (H2). It is made by passing steam over a red-hot carbon fuel such as coke. The reaction between steam and hydrocarbons produce the has mixture.
[20] Which of the following elements is obtained from sea weeds?
A.
Iodine
B.
Vanadium
C.
Argon
D.
Sulphur
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and anti-okidants, which help strengthen immunity.
[21] If there is one million Mg2+ ions in MgCl2, how many chloride ions are there?
A.
Two million
B.
One million
C.
Half a million
D.
Ten million
Ans:
Two million
Explanation :
Using formula of Stoichiometry, 1mol MgCl2 : 1mol Mg2+: 2mol Cl-. There are two moles of chloride ions for every one mole of MgCl2. So if there is one million Mg2+ ions in MgCl2, there will be two million chloride ions in it
[22] The gas that causes suffocation and death when coal or coke is burnt in a closed room is -
A.
Methane
B.
Ethane
C.
Carbon monoxide
D.
Carbon dioxide
Ans:
Carbon monoxide
Explanation :
Exhaust fumes of motor cars, gases produced, from coal fire in a closed room and coal gas, all contain carbon monoxide, which is the cause of their poisonous nature. When carbon monoxide is inhaled, it prevents the oxygen from combining with hemoglobin and instead combines itself with hemoglobin to form carboxyhaemoglobin, which is stable compound. This causes oxygen starvation in the body tissues and eventually causes death by suffocation.
[23] the correct formula for ammonium phosphate.
A.
N4H6PO4
B.
(NH4)3PO
C.
(NH4)3PO4
D.
(NH4)2PO4
Ans:
(NH4)3PO4
Explanation :
(NH4)3PO4 is a the chemical formula for ammonium phosphate. For more chemistry related queries log on to website world of chemicals.
[24] Teryleneisa condensation polymer of ethylene glycol and which acid?
A.
Benzoic Acid
B.
Salicylic acid
C.
Phthalic acid
D.
Terephthalic acid
Ans:
Terephthalic acid
Explanation :
Terylene is a co-polymer of ethylene glycol and Terephthalic acid. Also known as Dacron, it is prepared by the condensation polymerization of ethylene glycerol and. Terephthalic acid with elimination of water. The reaction is carried out at about 420-460 K in the presence of a catalyst consisting of a mixture of zinc acetate and antimony trioxide.
[25] Which of the following ores does not contain iron?
A.
Haematite
B.
Magnetite
C.
Limonite
D.
Cassiterite
Ans:
Cassiterite
Explanation :
Haematite is Fe2O3, magnetite is Fe3O4 and Magnesite is MgCO3. ∴ Magnesite is not ore of iron.
Explanation :
Higher concentration of Nitrogen and Phosphorus causes Eutrophication.
[6] The smallest particle of an element is called -
A.
Ion
B.
Electron
C.
Atom
D.
Molecule
Ans:
Atom
Explanation :
An element is a substance completely made up of one atom. However, the atom itself is not the smallest known particle, but instead each atom is made up of three individual parts: electrons, protons and neutrons.
[7] There are some substances whose odor changes in acidic or basic media. These are called -
A.
Olfactory indicators
B.
Litmus indicator
C.
Gustatory indicators
D.
All of the above
Ans:
Olfactory indicators
Explanation :
An Olfactory indicator is a substance whose smell varies depending on whether it is mixed with an acidic or basic solution. Onion , clove oil and vanilla extract are examples.
[8] Which of the following elements has the atomic number greater than that of Phosphorus?
A.
Aluminium
B.
Silicon
C.
Chlorine
D.
Magnesium
Ans:
Chlorine
Explanation :
Chlorine is a chemical element with symbol Cl and atomic number 17. Phosphorus is a chemical element with symbol P and atomic number 15.
[9] If the sewage is fully oxidized, the nitrogen is in the form of –
A.
Nitrites
B.
Ammonia
C.
Nitramines
D.
Nitrates
Ans:
Nitrates
Explanation :
Oxidized forms of nitrogen include nitrite (NO2) and nitrate (NO3). Nitrogen mainly occurs in wastewater in this form. Because nitrite is easily oxidized to nitrate, nitrate is the compound predominantly found in groundwater and surface waters.
[10] Which among the following is used to dilute oxygen in the gas cylinders used by divers?
A.
Krypton
B.
Argon
C.
Helium
D.
Neon
Ans:
Helium
Explanation :
Helium is used to dilute the oxygen and nitrogen to reduce these affects. Helium is the gas of choice to use because it is an inert gas, is thinner, therefore more compressible than air, and its narcotic properties are negligible in comparison to nitrogen.
[11] Which one of the following does not form oxyacid?
A.
Sulphur
B.
Chlorine
C.
Nitrogen
D.
Fluorine
Ans:
Fluorine
Explanation :
Fluorine cannot form oxyacid because fluorine is more electronegative than oxygen. For oxygen to bind, it must be a positively charged ion.
[12] The gas used to extinguish fire is –
A.
Neon
B.
Nitrogen
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon monoxide
Explanation :
Fires require these 3 things: a fuel (a hydrocarbon, which is a compound containing only carbon and hydrogen), a source of oxygen, and heal. Carbon Dioxide is most commonly used to extinguish fire as it displaces wwgen, thus choking the very source of a fire.
[13] _is not an allotrope of carbon.
A.
Buckminsterfullerene
B.
Carbon Doxide
C.
Diamond
D.
Graphite
Ans:
Carbon Doxide
Explanation :
Carbon is capable of forming many allotropes due to its valency. Well-known forms of carbon include diamond and graphite. Other allotropes in clude: include buckyballs (fullerenes), amorphous carbon, glassy carbon, carbon nanofoam, nanotubes,and others.
[14] Which hydrocarbons are the major constituents of 'LPG'?
A.
Methane and Ethane
B.
Propane and Butane
C.
Pentane and Benzene
D.
Only Methane
Ans:
Propane and Butane
Explanation :
Cooking gas, also known as Liquefied Petroleum Gas (LPG) is primarily propane (C3Hg) and butane (C4H10).
[15] When cathode rays strike a target of high atomic weight, they give rise to –
A.
α -rays
B.
β and γ rays
C.
X-rays
D.
positive rays
Ans:
X-rays
Explanation :
When cathode rays strike a solid target of high atomic weight and high melting point such as tungsten, molybdenum, etc, they give rise to a highly pen-etrating radiation called the X-rays (LIT Physics by Dr. P.K Aganval).
[16] The major use of sulphur is in the manufacture of –
A.
H2SO4
B.
H2S
C.
SO2
D.
Fungicide
Ans:
H2SO4
Explanation :
The major use of sulphur is in the manufacture of sulphuric acid (H2SO4) which is one of the most important compounds made by the chemical industry. It is used to make, literally, hundreds of compounds needed by almost every industry.
[17] Which of the following will replace hydrogen from acids to form salts?
A.
S
B.
Na
C.
Ag
D.
P
Ans:
Na
Explanation :
All acids contain hydrogen atom (s). Dilute acids react with some metals such as Sodium, Potassium, Calcium, iron, etc to form salts. Sodium replaces two hydrogen atoms from Sulfuric acid (H2SO4) to form a normal salt, Sodium Sulphate (Na2SO4).
[18] Which of the following metals has least, melting point?
A.
Gold
B.
Silver
C.
Mercury
D.
Copper
Ans:
Mercury
Explanation :
The melting point of the given metals (in Celsius) are:- Gold: 1063; Silver: 961; Copper: 1083; Mercury: - 38.86. Mercury is the only elemental metal known to melt at a generally cold temperature.
[19] Water gas is the combination of –
A.
CO and H2
B.
CO2 and H2
C.
CO and H2O
D.
CO2 and CO
Ans:
CO and H2
Explanation :
Water has is a synthesis gas, containing carbon monoxide (CO) and hydrogen has (H2). It is made by passing steam over a red-hot carbon fuel such as coke. The reaction between steam and hydrocarbons produce the has mixture.
[20] Which of the following elements is obtained from sea weeds?
A.
Iodine
B.
Vanadium
C.
Argon
D.
Sulphur
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and anti-okidants, which help strengthen immunity.
[21] If there is one million Mg2+ ions in MgCl2, how many chloride ions are there?
A.
Two million
B.
One million
C.
Half a million
D.
Ten million
Ans:
Two million
Explanation :
Using formula of Stoichiometry, 1mol MgCl2 : 1mol Mg2+: 2mol Cl-. There are two moles of chloride ions for every one mole of MgCl2. So if there is one million Mg2+ ions in MgCl2, there will be two million chloride ions in it
[22] The gas that causes suffocation and death when coal or coke is burnt in a closed room is -
A.
Methane
B.
Ethane
C.
Carbon monoxide
D.
Carbon dioxide
Ans:
Carbon monoxide
Explanation :
Exhaust fumes of motor cars, gases produced, from coal fire in a closed room and coal gas, all contain carbon monoxide, which is the cause of their poisonous nature. When carbon monoxide is inhaled, it prevents the oxygen from combining with hemoglobin and instead combines itself with hemoglobin to form carboxyhaemoglobin, which is stable compound. This causes oxygen starvation in the body tissues and eventually causes death by suffocation.
[23] the correct formula for ammonium phosphate.
A.
N4H6PO4
B.
(NH4)3PO
C.
(NH4)3PO4
D.
(NH4)2PO4
Ans:
(NH4)3PO4
Explanation :
(NH4)3PO4 is a the chemical formula for ammonium phosphate. For more chemistry related queries log on to website world of chemicals.
[24] Teryleneisa condensation polymer of ethylene glycol and which acid?
A.
Benzoic Acid
B.
Salicylic acid
C.
Phthalic acid
D.
Terephthalic acid
Ans:
Terephthalic acid
Explanation :
Terylene is a co-polymer of ethylene glycol and Terephthalic acid. Also known as Dacron, it is prepared by the condensation polymerization of ethylene glycerol and. Terephthalic acid with elimination of water. The reaction is carried out at about 420-460 K in the presence of a catalyst consisting of a mixture of zinc acetate and antimony trioxide.
[25] Which of the following ores does not contain iron?
A.
Haematite
B.
Magnetite
C.
Limonite
D.
Cassiterite
Ans:
Cassiterite
Explanation :
Haematite is Fe2O3, magnetite is Fe3O4 and Magnesite is MgCO3. ∴ Magnesite is not ore of iron.
Explanation :
An Olfactory indicator is a substance whose smell varies depending on whether it is mixed with an acidic or basic solution. Onion , clove oil and vanilla extract are examples.
[8] Which of the following elements has the atomic number greater than that of Phosphorus?
A.
Aluminium
B.
Silicon
C.
Chlorine
D.
Magnesium
Ans:
Chlorine
Explanation :
Chlorine is a chemical element with symbol Cl and atomic number 17. Phosphorus is a chemical element with symbol P and atomic number 15.
[9] If the sewage is fully oxidized, the nitrogen is in the form of –
A.
Nitrites
B.
Ammonia
C.
Nitramines
D.
Nitrates
Ans:
Nitrates
Explanation :
Oxidized forms of nitrogen include nitrite (NO2) and nitrate (NO3). Nitrogen mainly occurs in wastewater in this form. Because nitrite is easily oxidized to nitrate, nitrate is the compound predominantly found in groundwater and surface waters.
[10] Which among the following is used to dilute oxygen in the gas cylinders used by divers?
A.
Krypton
B.
Argon
C.
Helium
D.
Neon
Ans:
Helium
Explanation :
Helium is used to dilute the oxygen and nitrogen to reduce these affects. Helium is the gas of choice to use because it is an inert gas, is thinner, therefore more compressible than air, and its narcotic properties are negligible in comparison to nitrogen.
[11] Which one of the following does not form oxyacid?
A.
Sulphur
B.
Chlorine
C.
Nitrogen
D.
Fluorine
Ans:
Fluorine
Explanation :
Fluorine cannot form oxyacid because fluorine is more electronegative than oxygen. For oxygen to bind, it must be a positively charged ion.
[12] The gas used to extinguish fire is –
A.
Neon
B.
Nitrogen
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon monoxide
Explanation :
Fires require these 3 things: a fuel (a hydrocarbon, which is a compound containing only carbon and hydrogen), a source of oxygen, and heal. Carbon Dioxide is most commonly used to extinguish fire as it displaces wwgen, thus choking the very source of a fire.
[13] _is not an allotrope of carbon.
A.
Buckminsterfullerene
B.
Carbon Doxide
C.
Diamond
D.
Graphite
Ans:
Carbon Doxide
Explanation :
Carbon is capable of forming many allotropes due to its valency. Well-known forms of carbon include diamond and graphite. Other allotropes in clude: include buckyballs (fullerenes), amorphous carbon, glassy carbon, carbon nanofoam, nanotubes,and others.
[14] Which hydrocarbons are the major constituents of 'LPG'?
A.
Methane and Ethane
B.
Propane and Butane
C.
Pentane and Benzene
D.
Only Methane
Ans:
Propane and Butane
Explanation :
Cooking gas, also known as Liquefied Petroleum Gas (LPG) is primarily propane (C3Hg) and butane (C4H10).
[15] When cathode rays strike a target of high atomic weight, they give rise to –
A.
α -rays
B.
β and γ rays
C.
X-rays
D.
positive rays
Ans:
X-rays
Explanation :
When cathode rays strike a solid target of high atomic weight and high melting point such as tungsten, molybdenum, etc, they give rise to a highly pen-etrating radiation called the X-rays (LIT Physics by Dr. P.K Aganval).
[16] The major use of sulphur is in the manufacture of –
A.
H2SO4
B.
H2S
C.
SO2
D.
Fungicide
Ans:
H2SO4
Explanation :
The major use of sulphur is in the manufacture of sulphuric acid (H2SO4) which is one of the most important compounds made by the chemical industry. It is used to make, literally, hundreds of compounds needed by almost every industry.
[17] Which of the following will replace hydrogen from acids to form salts?
A.
S
B.
Na
C.
Ag
D.
P
Ans:
Na
Explanation :
All acids contain hydrogen atom (s). Dilute acids react with some metals such as Sodium, Potassium, Calcium, iron, etc to form salts. Sodium replaces two hydrogen atoms from Sulfuric acid (H2SO4) to form a normal salt, Sodium Sulphate (Na2SO4).
[18] Which of the following metals has least, melting point?
A.
Gold
B.
Silver
C.
Mercury
D.
Copper
Ans:
Mercury
Explanation :
The melting point of the given metals (in Celsius) are:- Gold: 1063; Silver: 961; Copper: 1083; Mercury: - 38.86. Mercury is the only elemental metal known to melt at a generally cold temperature.
[19] Water gas is the combination of –
A.
CO and H2
B.
CO2 and H2
C.
CO and H2O
D.
CO2 and CO
Ans:
CO and H2
Explanation :
Water has is a synthesis gas, containing carbon monoxide (CO) and hydrogen has (H2). It is made by passing steam over a red-hot carbon fuel such as coke. The reaction between steam and hydrocarbons produce the has mixture.
[20] Which of the following elements is obtained from sea weeds?
A.
Iodine
B.
Vanadium
C.
Argon
D.
Sulphur
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and anti-okidants, which help strengthen immunity.
[21] If there is one million Mg2+ ions in MgCl2, how many chloride ions are there?
A.
Two million
B.
One million
C.
Half a million
D.
Ten million
Ans:
Two million
Explanation :
Using formula of Stoichiometry, 1mol MgCl2 : 1mol Mg2+: 2mol Cl-. There are two moles of chloride ions for every one mole of MgCl2. So if there is one million Mg2+ ions in MgCl2, there will be two million chloride ions in it
[22] The gas that causes suffocation and death when coal or coke is burnt in a closed room is -
A.
Methane
B.
Ethane
C.
Carbon monoxide
D.
Carbon dioxide
Ans:
Carbon monoxide
Explanation :
Exhaust fumes of motor cars, gases produced, from coal fire in a closed room and coal gas, all contain carbon monoxide, which is the cause of their poisonous nature. When carbon monoxide is inhaled, it prevents the oxygen from combining with hemoglobin and instead combines itself with hemoglobin to form carboxyhaemoglobin, which is stable compound. This causes oxygen starvation in the body tissues and eventually causes death by suffocation.
[23] the correct formula for ammonium phosphate.
A.
N4H6PO4
B.
(NH4)3PO
C.
(NH4)3PO4
D.
(NH4)2PO4
Ans:
(NH4)3PO4
Explanation :
(NH4)3PO4 is a the chemical formula for ammonium phosphate. For more chemistry related queries log on to website world of chemicals.
[24] Teryleneisa condensation polymer of ethylene glycol and which acid?
A.
Benzoic Acid
B.
Salicylic acid
C.
Phthalic acid
D.
Terephthalic acid
Ans:
Terephthalic acid
Explanation :
Terylene is a co-polymer of ethylene glycol and Terephthalic acid. Also known as Dacron, it is prepared by the condensation polymerization of ethylene glycerol and. Terephthalic acid with elimination of water. The reaction is carried out at about 420-460 K in the presence of a catalyst consisting of a mixture of zinc acetate and antimony trioxide.
[25] Which of the following ores does not contain iron?
A.
Haematite
B.
Magnetite
C.
Limonite
D.
Cassiterite
Ans:
Cassiterite
Explanation :
Haematite is Fe2O3, magnetite is Fe3O4 and Magnesite is MgCO3. ∴ Magnesite is not ore of iron.
Explanation :
Oxidized forms of nitrogen include nitrite (NO2) and nitrate (NO3). Nitrogen mainly occurs in wastewater in this form. Because nitrite is easily oxidized to nitrate, nitrate is the compound predominantly found in groundwater and surface waters.
[10] Which among the following is used to dilute oxygen in the gas cylinders used by divers?
A.
Krypton
B.
Argon
C.
Helium
D.
Neon
Ans:
Helium
Explanation :
Helium is used to dilute the oxygen and nitrogen to reduce these affects. Helium is the gas of choice to use because it is an inert gas, is thinner, therefore more compressible than air, and its narcotic properties are negligible in comparison to nitrogen.
[11] Which one of the following does not form oxyacid?
A.
Sulphur
B.
Chlorine
C.
Nitrogen
D.
Fluorine
Ans:
Fluorine
Explanation :
Fluorine cannot form oxyacid because fluorine is more electronegative than oxygen. For oxygen to bind, it must be a positively charged ion.
[12] The gas used to extinguish fire is –
A.
Neon
B.
Nitrogen
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon monoxide
Explanation :
Fires require these 3 things: a fuel (a hydrocarbon, which is a compound containing only carbon and hydrogen), a source of oxygen, and heal. Carbon Dioxide is most commonly used to extinguish fire as it displaces wwgen, thus choking the very source of a fire.
[13] _is not an allotrope of carbon.
A.
Buckminsterfullerene
B.
Carbon Doxide
C.
Diamond
D.
Graphite
Ans:
Carbon Doxide
Explanation :
Carbon is capable of forming many allotropes due to its valency. Well-known forms of carbon include diamond and graphite. Other allotropes in clude: include buckyballs (fullerenes), amorphous carbon, glassy carbon, carbon nanofoam, nanotubes,and others.
[14] Which hydrocarbons are the major constituents of 'LPG'?
A.
Methane and Ethane
B.
Propane and Butane
C.
Pentane and Benzene
D.
Only Methane
Ans:
Propane and Butane
Explanation :
Cooking gas, also known as Liquefied Petroleum Gas (LPG) is primarily propane (C3Hg) and butane (C4H10).
[15] When cathode rays strike a target of high atomic weight, they give rise to –
A.
α -rays
B.
β and γ rays
C.
X-rays
D.
positive rays
Ans:
X-rays
Explanation :
When cathode rays strike a solid target of high atomic weight and high melting point such as tungsten, molybdenum, etc, they give rise to a highly pen-etrating radiation called the X-rays (LIT Physics by Dr. P.K Aganval).
[16] The major use of sulphur is in the manufacture of –
A.
H2SO4
B.
H2S
C.
SO2
D.
Fungicide
Ans:
H2SO4
Explanation :
The major use of sulphur is in the manufacture of sulphuric acid (H2SO4) which is one of the most important compounds made by the chemical industry. It is used to make, literally, hundreds of compounds needed by almost every industry.
[17] Which of the following will replace hydrogen from acids to form salts?
A.
S
B.
Na
C.
Ag
D.
P
Ans:
Na
Explanation :
All acids contain hydrogen atom (s). Dilute acids react with some metals such as Sodium, Potassium, Calcium, iron, etc to form salts. Sodium replaces two hydrogen atoms from Sulfuric acid (H2SO4) to form a normal salt, Sodium Sulphate (Na2SO4).
[18] Which of the following metals has least, melting point?
A.
Gold
B.
Silver
C.
Mercury
D.
Copper
Ans:
Mercury
Explanation :
The melting point of the given metals (in Celsius) are:- Gold: 1063; Silver: 961; Copper: 1083; Mercury: - 38.86. Mercury is the only elemental metal known to melt at a generally cold temperature.
[19] Water gas is the combination of –
A.
CO and H2
B.
CO2 and H2
C.
CO and H2O
D.
CO2 and CO
Ans:
CO and H2
Explanation :
Water has is a synthesis gas, containing carbon monoxide (CO) and hydrogen has (H2). It is made by passing steam over a red-hot carbon fuel such as coke. The reaction between steam and hydrocarbons produce the has mixture.
[20] Which of the following elements is obtained from sea weeds?
A.
Iodine
B.
Vanadium
C.
Argon
D.
Sulphur
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and anti-okidants, which help strengthen immunity.
[21] If there is one million Mg2+ ions in MgCl2, how many chloride ions are there?
A.
Two million
B.
One million
C.
Half a million
D.
Ten million
Ans:
Two million
Explanation :
Using formula of Stoichiometry, 1mol MgCl2 : 1mol Mg2+: 2mol Cl-. There are two moles of chloride ions for every one mole of MgCl2. So if there is one million Mg2+ ions in MgCl2, there will be two million chloride ions in it
[22] The gas that causes suffocation and death when coal or coke is burnt in a closed room is -
A.
Methane
B.
Ethane
C.
Carbon monoxide
D.
Carbon dioxide
Ans:
Carbon monoxide
Explanation :
Exhaust fumes of motor cars, gases produced, from coal fire in a closed room and coal gas, all contain carbon monoxide, which is the cause of their poisonous nature. When carbon monoxide is inhaled, it prevents the oxygen from combining with hemoglobin and instead combines itself with hemoglobin to form carboxyhaemoglobin, which is stable compound. This causes oxygen starvation in the body tissues and eventually causes death by suffocation.
[23] the correct formula for ammonium phosphate.
A.
N4H6PO4
B.
(NH4)3PO
C.
(NH4)3PO4
D.
(NH4)2PO4
Ans:
(NH4)3PO4
Explanation :
(NH4)3PO4 is a the chemical formula for ammonium phosphate. For more chemistry related queries log on to website world of chemicals.
[24] Teryleneisa condensation polymer of ethylene glycol and which acid?
A.
Benzoic Acid
B.
Salicylic acid
C.
Phthalic acid
D.
Terephthalic acid
Ans:
Terephthalic acid
Explanation :
Terylene is a co-polymer of ethylene glycol and Terephthalic acid. Also known as Dacron, it is prepared by the condensation polymerization of ethylene glycerol and. Terephthalic acid with elimination of water. The reaction is carried out at about 420-460 K in the presence of a catalyst consisting of a mixture of zinc acetate and antimony trioxide.
[25] Which of the following ores does not contain iron?
A.
Haematite
B.
Magnetite
C.
Limonite
D.
Cassiterite
Ans:
Cassiterite
Explanation :
Haematite is Fe2O3, magnetite is Fe3O4 and Magnesite is MgCO3. ∴ Magnesite is not ore of iron.
Explanation :
Fluorine cannot form oxyacid because fluorine is more electronegative than oxygen. For oxygen to bind, it must be a positively charged ion.
[12] The gas used to extinguish fire is –
A.
Neon
B.
Nitrogen
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon monoxide
Explanation :
Fires require these 3 things: a fuel (a hydrocarbon, which is a compound containing only carbon and hydrogen), a source of oxygen, and heal. Carbon Dioxide is most commonly used to extinguish fire as it displaces wwgen, thus choking the very source of a fire.
[13] _is not an allotrope of carbon.
A.
Buckminsterfullerene
B.
Carbon Doxide
C.
Diamond
D.
Graphite
Ans:
Carbon Doxide
Explanation :
Carbon is capable of forming many allotropes due to its valency. Well-known forms of carbon include diamond and graphite. Other allotropes in clude: include buckyballs (fullerenes), amorphous carbon, glassy carbon, carbon nanofoam, nanotubes,and others.
[14] Which hydrocarbons are the major constituents of 'LPG'?
A.
Methane and Ethane
B.
Propane and Butane
C.
Pentane and Benzene
D.
Only Methane
Ans:
Propane and Butane
Explanation :
Cooking gas, also known as Liquefied Petroleum Gas (LPG) is primarily propane (C3Hg) and butane (C4H10).
[15] When cathode rays strike a target of high atomic weight, they give rise to –
A.
α -rays
B.
β and γ rays
C.
X-rays
D.
positive rays
Ans:
X-rays
Explanation :
When cathode rays strike a solid target of high atomic weight and high melting point such as tungsten, molybdenum, etc, they give rise to a highly pen-etrating radiation called the X-rays (LIT Physics by Dr. P.K Aganval).
[16] The major use of sulphur is in the manufacture of –
A.
H2SO4
B.
H2S
C.
SO2
D.
Fungicide
Ans:
H2SO4
Explanation :
The major use of sulphur is in the manufacture of sulphuric acid (H2SO4) which is one of the most important compounds made by the chemical industry. It is used to make, literally, hundreds of compounds needed by almost every industry.
[17] Which of the following will replace hydrogen from acids to form salts?
A.
S
B.
Na
C.
Ag
D.
P
Ans:
Na
Explanation :
All acids contain hydrogen atom (s). Dilute acids react with some metals such as Sodium, Potassium, Calcium, iron, etc to form salts. Sodium replaces two hydrogen atoms from Sulfuric acid (H2SO4) to form a normal salt, Sodium Sulphate (Na2SO4).
[18] Which of the following metals has least, melting point?
A.
Gold
B.
Silver
C.
Mercury
D.
Copper
Ans:
Mercury
Explanation :
The melting point of the given metals (in Celsius) are:- Gold: 1063; Silver: 961; Copper: 1083; Mercury: - 38.86. Mercury is the only elemental metal known to melt at a generally cold temperature.
[19] Water gas is the combination of –
A.
CO and H2
B.
CO2 and H2
C.
CO and H2O
D.
CO2 and CO
Ans:
CO and H2
Explanation :
Water has is a synthesis gas, containing carbon monoxide (CO) and hydrogen has (H2). It is made by passing steam over a red-hot carbon fuel such as coke. The reaction between steam and hydrocarbons produce the has mixture.
[20] Which of the following elements is obtained from sea weeds?
A.
Iodine
B.
Vanadium
C.
Argon
D.
Sulphur
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and anti-okidants, which help strengthen immunity.
[21] If there is one million Mg2+ ions in MgCl2, how many chloride ions are there?
A.
Two million
B.
One million
C.
Half a million
D.
Ten million
Ans:
Two million
Explanation :
Using formula of Stoichiometry, 1mol MgCl2 : 1mol Mg2+: 2mol Cl-. There are two moles of chloride ions for every one mole of MgCl2. So if there is one million Mg2+ ions in MgCl2, there will be two million chloride ions in it
[22] The gas that causes suffocation and death when coal or coke is burnt in a closed room is -
A.
Methane
B.
Ethane
C.
Carbon monoxide
D.
Carbon dioxide
Ans:
Carbon monoxide
Explanation :
Exhaust fumes of motor cars, gases produced, from coal fire in a closed room and coal gas, all contain carbon monoxide, which is the cause of their poisonous nature. When carbon monoxide is inhaled, it prevents the oxygen from combining with hemoglobin and instead combines itself with hemoglobin to form carboxyhaemoglobin, which is stable compound. This causes oxygen starvation in the body tissues and eventually causes death by suffocation.
[23] the correct formula for ammonium phosphate.
A.
N4H6PO4
B.
(NH4)3PO
C.
(NH4)3PO4
D.
(NH4)2PO4
Ans:
(NH4)3PO4
Explanation :
(NH4)3PO4 is a the chemical formula for ammonium phosphate. For more chemistry related queries log on to website world of chemicals.
[24] Teryleneisa condensation polymer of ethylene glycol and which acid?
A.
Benzoic Acid
B.
Salicylic acid
C.
Phthalic acid
D.
Terephthalic acid
Ans:
Terephthalic acid
Explanation :
Terylene is a co-polymer of ethylene glycol and Terephthalic acid. Also known as Dacron, it is prepared by the condensation polymerization of ethylene glycerol and. Terephthalic acid with elimination of water. The reaction is carried out at about 420-460 K in the presence of a catalyst consisting of a mixture of zinc acetate and antimony trioxide.
[25] Which of the following ores does not contain iron?
A.
Haematite
B.
Magnetite
C.
Limonite
D.
Cassiterite
Ans:
Cassiterite
Explanation :
Haematite is Fe2O3, magnetite is Fe3O4 and Magnesite is MgCO3. ∴ Magnesite is not ore of iron.
Explanation :
Carbon is capable of forming many allotropes due to its valency. Well-known forms of carbon include diamond and graphite. Other allotropes in clude: include buckyballs (fullerenes), amorphous carbon, glassy carbon, carbon nanofoam, nanotubes,and others.
[14] Which hydrocarbons are the major constituents of 'LPG'?
A.
Methane and Ethane
B.
Propane and Butane
C.
Pentane and Benzene
D.
Only Methane
Ans:
Propane and Butane
Explanation :
Cooking gas, also known as Liquefied Petroleum Gas (LPG) is primarily propane (C3Hg) and butane (C4H10).
[15] When cathode rays strike a target of high atomic weight, they give rise to –
A.
α -rays
B.
β and γ rays
C.
X-rays
D.
positive rays
Ans:
X-rays
Explanation :
When cathode rays strike a solid target of high atomic weight and high melting point such as tungsten, molybdenum, etc, they give rise to a highly pen-etrating radiation called the X-rays (LIT Physics by Dr. P.K Aganval).
[16] The major use of sulphur is in the manufacture of –
A.
H2SO4
B.
H2S
C.
SO2
D.
Fungicide
Ans:
H2SO4
Explanation :
The major use of sulphur is in the manufacture of sulphuric acid (H2SO4) which is one of the most important compounds made by the chemical industry. It is used to make, literally, hundreds of compounds needed by almost every industry.
[17] Which of the following will replace hydrogen from acids to form salts?
A.
S
B.
Na
C.
Ag
D.
P
Ans:
Na
Explanation :
All acids contain hydrogen atom (s). Dilute acids react with some metals such as Sodium, Potassium, Calcium, iron, etc to form salts. Sodium replaces two hydrogen atoms from Sulfuric acid (H2SO4) to form a normal salt, Sodium Sulphate (Na2SO4).
[18] Which of the following metals has least, melting point?
A.
Gold
B.
Silver
C.
Mercury
D.
Copper
Ans:
Mercury
Explanation :
The melting point of the given metals (in Celsius) are:- Gold: 1063; Silver: 961; Copper: 1083; Mercury: - 38.86. Mercury is the only elemental metal known to melt at a generally cold temperature.
[19] Water gas is the combination of –
A.
CO and H2
B.
CO2 and H2
C.
CO and H2O
D.
CO2 and CO
Ans:
CO and H2
Explanation :
Water has is a synthesis gas, containing carbon monoxide (CO) and hydrogen has (H2). It is made by passing steam over a red-hot carbon fuel such as coke. The reaction between steam and hydrocarbons produce the has mixture.
[20] Which of the following elements is obtained from sea weeds?
A.
Iodine
B.
Vanadium
C.
Argon
D.
Sulphur
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and anti-okidants, which help strengthen immunity.
[21] If there is one million Mg2+ ions in MgCl2, how many chloride ions are there?
A.
Two million
B.
One million
C.
Half a million
D.
Ten million
Ans:
Two million
Explanation :
Using formula of Stoichiometry, 1mol MgCl2 : 1mol Mg2+: 2mol Cl-. There are two moles of chloride ions for every one mole of MgCl2. So if there is one million Mg2+ ions in MgCl2, there will be two million chloride ions in it
[22] The gas that causes suffocation and death when coal or coke is burnt in a closed room is -
A.
Methane
B.
Ethane
C.
Carbon monoxide
D.
Carbon dioxide
Ans:
Carbon monoxide
Explanation :
Exhaust fumes of motor cars, gases produced, from coal fire in a closed room and coal gas, all contain carbon monoxide, which is the cause of their poisonous nature. When carbon monoxide is inhaled, it prevents the oxygen from combining with hemoglobin and instead combines itself with hemoglobin to form carboxyhaemoglobin, which is stable compound. This causes oxygen starvation in the body tissues and eventually causes death by suffocation.
[23] the correct formula for ammonium phosphate.
A.
N4H6PO4
B.
(NH4)3PO
C.
(NH4)3PO4
D.
(NH4)2PO4
Ans:
(NH4)3PO4
Explanation :
(NH4)3PO4 is a the chemical formula for ammonium phosphate. For more chemistry related queries log on to website world of chemicals.
[24] Teryleneisa condensation polymer of ethylene glycol and which acid?
A.
Benzoic Acid
B.
Salicylic acid
C.
Phthalic acid
D.
Terephthalic acid
Ans:
Terephthalic acid
Explanation :
Terylene is a co-polymer of ethylene glycol and Terephthalic acid. Also known as Dacron, it is prepared by the condensation polymerization of ethylene glycerol and. Terephthalic acid with elimination of water. The reaction is carried out at about 420-460 K in the presence of a catalyst consisting of a mixture of zinc acetate and antimony trioxide.
[25] Which of the following ores does not contain iron?
A.
Haematite
B.
Magnetite
C.
Limonite
D.
Cassiterite
Ans:
Cassiterite
Explanation :
Haematite is Fe2O3, magnetite is Fe3O4 and Magnesite is MgCO3. ∴ Magnesite is not ore of iron.
Explanation :
When cathode rays strike a solid target of high atomic weight and high melting point such as tungsten, molybdenum, etc, they give rise to a highly pen-etrating radiation called the X-rays (LIT Physics by Dr. P.K Aganval).
[16] The major use of sulphur is in the manufacture of –
A.
H2SO4
B.
H2S
C.
SO2
D.
Fungicide
Ans:
H2SO4
Explanation :
The major use of sulphur is in the manufacture of sulphuric acid (H2SO4) which is one of the most important compounds made by the chemical industry. It is used to make, literally, hundreds of compounds needed by almost every industry.
[17] Which of the following will replace hydrogen from acids to form salts?
A.
S
B.
Na
C.
Ag
D.
P
Ans:
Na
Explanation :
All acids contain hydrogen atom (s). Dilute acids react with some metals such as Sodium, Potassium, Calcium, iron, etc to form salts. Sodium replaces two hydrogen atoms from Sulfuric acid (H2SO4) to form a normal salt, Sodium Sulphate (Na2SO4).
[18] Which of the following metals has least, melting point?
A.
Gold
B.
Silver
C.
Mercury
D.
Copper
Ans:
Mercury
Explanation :
The melting point of the given metals (in Celsius) are:- Gold: 1063; Silver: 961; Copper: 1083; Mercury: - 38.86. Mercury is the only elemental metal known to melt at a generally cold temperature.
[19] Water gas is the combination of –
A.
CO and H2
B.
CO2 and H2
C.
CO and H2O
D.
CO2 and CO
Ans:
CO and H2
Explanation :
Water has is a synthesis gas, containing carbon monoxide (CO) and hydrogen has (H2). It is made by passing steam over a red-hot carbon fuel such as coke. The reaction between steam and hydrocarbons produce the has mixture.
[20] Which of the following elements is obtained from sea weeds?
A.
Iodine
B.
Vanadium
C.
Argon
D.
Sulphur
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and anti-okidants, which help strengthen immunity.
[21] If there is one million Mg2+ ions in MgCl2, how many chloride ions are there?
A.
Two million
B.
One million
C.
Half a million
D.
Ten million
Ans:
Two million
Explanation :
Using formula of Stoichiometry, 1mol MgCl2 : 1mol Mg2+: 2mol Cl-. There are two moles of chloride ions for every one mole of MgCl2. So if there is one million Mg2+ ions in MgCl2, there will be two million chloride ions in it
[22] The gas that causes suffocation and death when coal or coke is burnt in a closed room is -
A.
Methane
B.
Ethane
C.
Carbon monoxide
D.
Carbon dioxide
Ans:
Carbon monoxide
Explanation :
Exhaust fumes of motor cars, gases produced, from coal fire in a closed room and coal gas, all contain carbon monoxide, which is the cause of their poisonous nature. When carbon monoxide is inhaled, it prevents the oxygen from combining with hemoglobin and instead combines itself with hemoglobin to form carboxyhaemoglobin, which is stable compound. This causes oxygen starvation in the body tissues and eventually causes death by suffocation.
[23] the correct formula for ammonium phosphate.
A.
N4H6PO4
B.
(NH4)3PO
C.
(NH4)3PO4
D.
(NH4)2PO4
Ans:
(NH4)3PO4
Explanation :
(NH4)3PO4 is a the chemical formula for ammonium phosphate. For more chemistry related queries log on to website world of chemicals.
[24] Teryleneisa condensation polymer of ethylene glycol and which acid?
A.
Benzoic Acid
B.
Salicylic acid
C.
Phthalic acid
D.
Terephthalic acid
Ans:
Terephthalic acid
Explanation :
Terylene is a co-polymer of ethylene glycol and Terephthalic acid. Also known as Dacron, it is prepared by the condensation polymerization of ethylene glycerol and. Terephthalic acid with elimination of water. The reaction is carried out at about 420-460 K in the presence of a catalyst consisting of a mixture of zinc acetate and antimony trioxide.
[25] Which of the following ores does not contain iron?
A.
Haematite
B.
Magnetite
C.
Limonite
D.
Cassiterite
Ans:
Cassiterite
Explanation :
Haematite is Fe2O3, magnetite is Fe3O4 and Magnesite is MgCO3. ∴ Magnesite is not ore of iron.
Explanation :
All acids contain hydrogen atom (s). Dilute acids react with some metals such as Sodium, Potassium, Calcium, iron, etc to form salts. Sodium replaces two hydrogen atoms from Sulfuric acid (H2SO4) to form a normal salt, Sodium Sulphate (Na2SO4).
[18] Which of the following metals has least, melting point?
A.
Gold
B.
Silver
C.
Mercury
D.
Copper
Ans:
Mercury
Explanation :
The melting point of the given metals (in Celsius) are:- Gold: 1063; Silver: 961; Copper: 1083; Mercury: - 38.86. Mercury is the only elemental metal known to melt at a generally cold temperature.
[19] Water gas is the combination of –
A.
CO and H2
B.
CO2 and H2
C.
CO and H2O
D.
CO2 and CO
Ans:
CO and H2
Explanation :
Water has is a synthesis gas, containing carbon monoxide (CO) and hydrogen has (H2). It is made by passing steam over a red-hot carbon fuel such as coke. The reaction between steam and hydrocarbons produce the has mixture.
[20] Which of the following elements is obtained from sea weeds?
A.
Iodine
B.
Vanadium
C.
Argon
D.
Sulphur
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and anti-okidants, which help strengthen immunity.
[21] If there is one million Mg2+ ions in MgCl2, how many chloride ions are there?
A.
Two million
B.
One million
C.
Half a million
D.
Ten million
Ans:
Two million
Explanation :
Using formula of Stoichiometry, 1mol MgCl2 : 1mol Mg2+: 2mol Cl-. There are two moles of chloride ions for every one mole of MgCl2. So if there is one million Mg2+ ions in MgCl2, there will be two million chloride ions in it
[22] The gas that causes suffocation and death when coal or coke is burnt in a closed room is -
A.
Methane
B.
Ethane
C.
Carbon monoxide
D.
Carbon dioxide
Ans:
Carbon monoxide
Explanation :
Exhaust fumes of motor cars, gases produced, from coal fire in a closed room and coal gas, all contain carbon monoxide, which is the cause of their poisonous nature. When carbon monoxide is inhaled, it prevents the oxygen from combining with hemoglobin and instead combines itself with hemoglobin to form carboxyhaemoglobin, which is stable compound. This causes oxygen starvation in the body tissues and eventually causes death by suffocation.
[23] the correct formula for ammonium phosphate.
A.
N4H6PO4
B.
(NH4)3PO
C.
(NH4)3PO4
D.
(NH4)2PO4
Ans:
(NH4)3PO4
Explanation :
(NH4)3PO4 is a the chemical formula for ammonium phosphate. For more chemistry related queries log on to website world of chemicals.
[24] Teryleneisa condensation polymer of ethylene glycol and which acid?
A.
Benzoic Acid
B.
Salicylic acid
C.
Phthalic acid
D.
Terephthalic acid
Ans:
Terephthalic acid
Explanation :
Terylene is a co-polymer of ethylene glycol and Terephthalic acid. Also known as Dacron, it is prepared by the condensation polymerization of ethylene glycerol and. Terephthalic acid with elimination of water. The reaction is carried out at about 420-460 K in the presence of a catalyst consisting of a mixture of zinc acetate and antimony trioxide.
[25] Which of the following ores does not contain iron?
A.
Haematite
B.
Magnetite
C.
Limonite
D.
Cassiterite
Ans:
Cassiterite
Explanation :
Haematite is Fe2O3, magnetite is Fe3O4 and Magnesite is MgCO3. ∴ Magnesite is not ore of iron.
Explanation :
Water has is a synthesis gas, containing carbon monoxide (CO) and hydrogen has (H2). It is made by passing steam over a red-hot carbon fuel such as coke. The reaction between steam and hydrocarbons produce the has mixture.
[20] Which of the following elements is obtained from sea weeds?
A.
Iodine
B.
Vanadium
C.
Argon
D.
Sulphur
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and anti-okidants, which help strengthen immunity.
[21] If there is one million Mg2+ ions in MgCl2, how many chloride ions are there?
A.
Two million
B.
One million
C.
Half a million
D.
Ten million
Ans:
Two million
Explanation :
Using formula of Stoichiometry, 1mol MgCl2 : 1mol Mg2+: 2mol Cl-. There are two moles of chloride ions for every one mole of MgCl2. So if there is one million Mg2+ ions in MgCl2, there will be two million chloride ions in it
[22] The gas that causes suffocation and death when coal or coke is burnt in a closed room is -
A.
Methane
B.
Ethane
C.
Carbon monoxide
D.
Carbon dioxide
Ans:
Carbon monoxide
Explanation :
Exhaust fumes of motor cars, gases produced, from coal fire in a closed room and coal gas, all contain carbon monoxide, which is the cause of their poisonous nature. When carbon monoxide is inhaled, it prevents the oxygen from combining with hemoglobin and instead combines itself with hemoglobin to form carboxyhaemoglobin, which is stable compound. This causes oxygen starvation in the body tissues and eventually causes death by suffocation.
[23] the correct formula for ammonium phosphate.
A.
N4H6PO4
B.
(NH4)3PO
C.
(NH4)3PO4
D.
(NH4)2PO4
Ans:
(NH4)3PO4
Explanation :
(NH4)3PO4 is a the chemical formula for ammonium phosphate. For more chemistry related queries log on to website world of chemicals.
[24] Teryleneisa condensation polymer of ethylene glycol and which acid?
A.
Benzoic Acid
B.
Salicylic acid
C.
Phthalic acid
D.
Terephthalic acid
Ans:
Terephthalic acid
Explanation :
Terylene is a co-polymer of ethylene glycol and Terephthalic acid. Also known as Dacron, it is prepared by the condensation polymerization of ethylene glycerol and. Terephthalic acid with elimination of water. The reaction is carried out at about 420-460 K in the presence of a catalyst consisting of a mixture of zinc acetate and antimony trioxide.
[25] Which of the following ores does not contain iron?
A.
Haematite
B.
Magnetite
C.
Limonite
D.
Cassiterite
Ans:
Cassiterite
Explanation :
Haematite is Fe2O3, magnetite is Fe3O4 and Magnesite is MgCO3. ∴ Magnesite is not ore of iron.
Explanation :
Using formula of Stoichiometry, 1mol MgCl2 : 1mol Mg2+: 2mol Cl-. There are two moles of chloride ions for every one mole of MgCl2. So if there is one million Mg2+ ions in MgCl2, there will be two million chloride ions in it
[22] The gas that causes suffocation and death when coal or coke is burnt in a closed room is -
A.
Methane
B.
Ethane
C.
Carbon monoxide
D.
Carbon dioxide
Ans:
Carbon monoxide
Explanation :
Exhaust fumes of motor cars, gases produced, from coal fire in a closed room and coal gas, all contain carbon monoxide, which is the cause of their poisonous nature. When carbon monoxide is inhaled, it prevents the oxygen from combining with hemoglobin and instead combines itself with hemoglobin to form carboxyhaemoglobin, which is stable compound. This causes oxygen starvation in the body tissues and eventually causes death by suffocation.
[23] the correct formula for ammonium phosphate.
A.
N4H6PO4
B.
(NH4)3PO
C.
(NH4)3PO4
D.
(NH4)2PO4
Ans:
(NH4)3PO4
Explanation :
(NH4)3PO4 is a the chemical formula for ammonium phosphate. For more chemistry related queries log on to website world of chemicals.
[24] Teryleneisa condensation polymer of ethylene glycol and which acid?
A.
Benzoic Acid
B.
Salicylic acid
C.
Phthalic acid
D.
Terephthalic acid
Ans:
Terephthalic acid
Explanation :
Terylene is a co-polymer of ethylene glycol and Terephthalic acid. Also known as Dacron, it is prepared by the condensation polymerization of ethylene glycerol and. Terephthalic acid with elimination of water. The reaction is carried out at about 420-460 K in the presence of a catalyst consisting of a mixture of zinc acetate and antimony trioxide.
[25] Which of the following ores does not contain iron?
A.
Haematite
B.
Magnetite
C.
Limonite
D.
Cassiterite
Ans:
Cassiterite
Explanation :
Haematite is Fe2O3, magnetite is Fe3O4 and Magnesite is MgCO3. ∴ Magnesite is not ore of iron.
Explanation :
(NH4)3PO4 is a the chemical formula for ammonium phosphate. For more chemistry related queries log on to website world of chemicals.
[24] Teryleneisa condensation polymer of ethylene glycol and which acid?
A.
Benzoic Acid
B.
Salicylic acid
C.
Phthalic acid
D.
Terephthalic acid
Ans:
Terephthalic acid
Explanation :
Terylene is a co-polymer of ethylene glycol and Terephthalic acid. Also known as Dacron, it is prepared by the condensation polymerization of ethylene glycerol and. Terephthalic acid with elimination of water. The reaction is carried out at about 420-460 K in the presence of a catalyst consisting of a mixture of zinc acetate and antimony trioxide.
[25] Which of the following ores does not contain iron?
A.
Haematite
B.
Magnetite
C.
Limonite
D.
Cassiterite
Ans:
Cassiterite
Explanation :
Haematite is Fe2O3, magnetite is Fe3O4 and Magnesite is MgCO3. ∴ Magnesite is not ore of iron.
Explanation :
Haematite is Fe2O3, magnetite is Fe3O4 and Magnesite is MgCO3. ∴ Magnesite is not ore of iron.