501) Which hydrocarbons are the major constituents of 'LPG'?
Answer
Propane and Butane
502) When cathode rays strike a target of high atomic weight, they give rise to –
Answer
X-rays
503) The major use of sulphur is in the manufacture of –
Answer
H2SO4
504) Water gas is the combination of –
Answer
CO and H2
505) If there is one million Mg2+ ions in MgCl2, how many chloride ions are there?
Answer
Two million
506) The gas that causes suffocation and death when coal or coke is burnt in a closed room is -
Answer
Carbon monoxide
507) the correct formula for ammonium phosphate.
Answer
(NH4)3PO4
508) Teryleneisa condensation polymer of ethylene glycol and which acid?
Answer
Terephthalic acid
509) Acids generate:
Answer
Both are correct
510) When iron rusts, its weight –
Answer
increases
511) Nylon threads are made of -
Answer
Polyamide polymer
512) The manufacturing of iron from ironore involves the process of -
Answer
Reduction
513) isotope is used in the treatment of which disease?
Answer
cancer
514) The characteristic odour of garlic is due to -
Answer
a sulphur compound
515) An emulsion is a colloidal solution of -
Answer
Liquid in liquid
516) is a by product of sewage treatment and can be decomposed to produce biogas.
Answer
Sludge
517) Silver gets corroded due to in air.
Answer
Hydrogen Sulphide
518) Whatis Zeolite?
Answer
Hydrated Aluminosilicate
519) L.P.G. is mostly liquefied
Answer
butane
520) Which have the maximum density?
Answer
Water
521) Atoms having the same number of protons but different number of neutrons are called :
Answer
Isotopes
522) Organic compounds are -
Answer
Covalent compounds
523) Compounds of carbon having double or triple bonds between their carbon atoms are called -
Answer
Unsaturated compounds
524) An alloy used in making heating elements for electric heating device is -
Answer
Nichrome
525) The degree of dissociation of an electrolyte depends on -
Answer
dilution
526) Glass is mainly composed of -
Answer
Sodium silicate
527) A matured mammalian cell without nucleus is –
Answer
Erythrocyte
528) The most common cause of pollution of air is –
Answer
Sulphur dioxide
529) The main source of carbon monoxide is -
Answer
Transportation
530) Tooth enamel is the hardest substance found in the human body. What is it made up of -
Answer
Calcium phosphate
531) A solution turns blue litmus red, its pH is likely to be -
Answer
5
532) Brass gets discoloured in air due to constant exposure in presence of:
Answer
Hydrogen sulphide
533) Neutrons are slowed down in a nuclear reactor by –
Answer
Moderator
534) An element of atomic no. 29 belongs to –
Answer
d-block
535) Mechanical energy is the combination of kinetic energy and .
Answer
Potential energy
536) Magnetism at the centre of a bar magnet is -
Answer
zero
537) Substances that cause a reaction to occur or proceed at a different rate without the reaction itself being affected are called -
Answer
Catalysts
538) Poison used for killing rats is –
Answer
Zinc phosphide (Zn3P2)
539) The commonly used safety fuse-wire is made of -
Answer
an alloy of Tin and Lead
540) Lead pencil contains -
Answer
Graphite
541) The most suitable unit for expressing nuclear radius is -
Answer
fermi
542) The catalyst used in hydrogenation of oils is -
Answer
Ni
543) What is used in storage batteries?
Answer
Lead
544) Ozone saves the biosphere by absorbing high energy radiations called -
Answer
Ultraviolet rays (UV)
545) Silica gel is a -
Answer
drying agent
546) Neutron was discovered by -
Answer
Chadwick
547) Iodine can be separated from a mixture of Iodine and Potassium Chloride by -
Answer
Sublimation
548) Biofertilizers convert nitrogen to .
Answer
ammonia
549) Radioactivity was discovered by _.
Answer
H.Becquerel
550) gives hardness to stainless steel.
Answer
Carbon
551) Isotopes differ in -
Answer
No. of neutrons
552) Modern periodic law had been given by -
Answer
Moseley
553) Iron filings can be separated from a heterogenous mixture using the technique of :
Answer
Magnetization
554) The most abundant element by number in the living system is :
Answer
Hydrogen
555) Who discovered Potassium?
Answer
Humphry Davy
556) Air is -
Answer
Mixture
557) What is the formula of potassium ion in the noble gas state?
Answer
K⁺
558) Bauxite is used as raw material by which industry?
Answer
Aluminium
559) The element absorbed both in cation and anion form is –
Answer
Nitrogen
560) Browning of paper in old books is caused by –
Answer
oxidation of cellulose
561) Nuclear sizes are expressed in a unit named -
Answer
Fermi
562) The contact process is involved in the manufacture of -
Answer
Sulphuric acid
563) Brass is made of –
Answer
copper and zinc
564) The wine is prepared by the process of -
Answer
fermentation
565) Compounds with identical molecular formula but different structures are called -
Answer
Structural isomers
566) PVC is formed by polymerization of -
Answer
Vinyl Chloride
567) The unit to measure the flow of water is -
Answer
Cusecs
568) Copper is refined by -
Answer
roasting
569) What is the common name of CaOCI2?
Answer
Bleaching Powder
570) Rutherford’s scattering experiment proved the presence of -
Answer
nucleusin atoms
571) When a metal is heated in a flame, the electrons absorb energy and jump to higher energy state. On coming back to the lower energy state, they emit light, which we can observe in -
Answer
Emission spectra
572) Acid used in an automobile battery?
Answer
Sulphuric acid
573) In deep-sea diving, divers use a mixture of gases consisting of oxygen and –
Answer
nitrogen
574) Nucleons are regarded as composites sub-particles known as –
Answer
Quarks
575) If Metal A displaces Metal B from its solution, then Metal A _.
Answer
is more reactive than B
576) Who discovered electrons?
Answer
JJ Thomson
577) Which is also called Stranger Gas?
Answer
Xenon
578) Silicon is an example of -
Answer
A metalloid
579) The “King of Metals” is :
Answer
Gold
580) A mixture of carbon monoxide and hydrogen is called -
Answer
Water gas
581) In Nuclear reactors graphite is used as -
Answer
Modulator
582) Activated Charcoal is used to remove colouring matter from pure substances by –
Answer
Adsorption
583) Chernobyl disaster is the result of pollution by –
Answer
Radioactive waste
584) Bone deformities occur due to excessive intake of:
Answer
Fluorine
585) The name of the scientist who discovered neutron is -
Answer
Chadwick
586) Bronze is an alloy of –
Answer
Copper & tin
587) Which acid is used in Lead storage batteiy?
Answer
Sulphuric acid
588) Ethanoic acid is commonly called -
Answer
Acetic acid
589) The bubbles in Chanmpagne and Soda are -
Answer
Hydrogen
590) Which one is not metal?
Answer
all
591) What nucleus of atom contains?
Answer
protons and neutrons
592) For extinguishing fire, we use –
Answer
Carbon Dioxide
593) The main component of liquid bleach is:
Answer
Sodium hypochlorite
594) The chemical used as a fixer in photography is -
Answer
sodium thiosulphate
595) Which compound is formed when a Magnesium ribbon is burnt in air?
Answer
Magnesium Oxide
596) Nuclear fission is caused by the impact of.
Answer
Neutron
597) Interveinal necrotic spots on leaves appear due to –
Answer
SO2 injury
598) The pollutant responsible for ozone holes is -
Answer
CFC
599) Atomic themy of matter was given by –
Answer
Dalton
600) The major component in the LPG is -
Answer
butane
601) Carbon dioxide is –
Answer
a reducing agent
602) An atom of an element has atomic number 17 and mass number 36. The number of neutrons in its nucleus is–
Answer
19
603) The most reactive among the halogens is -
Answer
Fluorine
604) Black lung disease occurs in people working in –
Answer
Coal mines
605) NaCI has .
Answer
Ionic bonds
606) The metal used to recover copper from a solution of copper sulfate is -
Answer
Fe
607) The oxidation number of nickel in K4[Ni(CN)4] is -
Answer
Zero
608) The rusting of iron is a/an -
Answer
electrochemical change
609) Ethanol containing 5% water is known as –
Answer
Rectified spirit
610) Stains of rust on clothes can be removed by –
Answer
Oxalic acid
611) If a solution turns blue litmus red, its pH is likely to be :
Answer
6
612) An element with an atomic number of 17 is -
Answer
a halogen gas
613) The highest volume of gases in lower atmosphere is comprised of -
Answer
Nitrogen
614) The alkoloid naturally found in coffee, cocoa and cola nut is –
Answer
Caffeine
615) The metal used for making air crafts and rockets is –
Answer
Nickel
616) At what temperature is the density of water the maximum?
Answer
4°C
617) Soil having high content of aluminum and iron oxide is also known as -
Answer
pedalfer soil
618) Chile saltpeter is the common name of:
Answer
Sodium nitrate
619) The gas liberated in the Bhopal gas tragedy was:
Answer
Methyl isocynate
620) At room temperature, the metal that remains liquid is:
Answer
Mercury
621) The chemical name or guartz is –
Answer
Sodium silicate
622) The depletion in Ozone layer is caused by -
Answer
Chlorofluorocarbons
623) The isotope atoms differ in -
Answer
number of neutrons
624) This substance is sweet-smelling and is used in making perfumes and flavouring agents. It is called-
Answer
Ester
625) An acid is a substance which .
Answer
All
626) The most abundant element in the earth's atmosphere is –
Answer
Nitrogen
627) Chemical composition of cement is –
Answer
Limestone, Clay and Gypsum
628) Non-metallic character increases from -
Answer
Sodium to Chlorine
629) In organic compounds, nitrogen is estimates by -
Answer
Dumas method
630) Which one is the pure element?
Answer
sodium
631) Which is Known as carbolic acid?
Answer
Phenol
632) Atomic explosion is triggered by -
Answer
uncontrolled chain reaction
633) Stalactites and Stalagmites form due to the precipitation of :
Answer
CaCO3
634) Fullerenes form a class of carbon allotropes. The first one to be identified was -
Answer
C-60
635) The gas produced in marshy places due to decomposition of vegetation is –
Answer
Methane
636) The chemical name of "Hypo" commonly used in photography is –
Answer
Sodium thiosulphate
637) The process of improving the quality of rubber by heating it with sulphur is called.
Answer
Vulcanization
638) Piped Natural Gas (PNG) is used for –
Answer
Cooking
639) Which of the inert gases can form compounds?
Answer
Xenon
640) Burning pyrites ore gives out –
Answer
Sulphur dioxide gas
641) Milk is -
Answer
Emulsion
642) Compound having tetrahedral structure is .
Answer
CH4
643) Benzene cannot undergo –
Answer
Elinthaation
644) The polymer obtained by the condensation of hexamethylene diamine and adipic acid is –
Answer
Nylon 66
645) The antiseptic compound present in dettol is –
Answer
Enloroxylenol
646) Amniocentesis is a technique used -
Answer
to determine the sex of fetus
647) Bonds formed by the sharing of an electron pair between two atoms are known as -
Answer
Covalent bonds
648) The pH of lemon juice is expected to be –
Answer
less than 7
649) An example of heterocyclic compound is –
Answer
Furan
650) The pair of compounds used as anesthetic in medicines –
Answer
Nitrous oxide, Chloroform
651) pH scale ranges from –
Answer
0 - 14
652) Glass is -
Answer
Super cooled liquid
653) The sum of potential energy and kinetic energy is known as :
Answer
Mechanical energy
654) Carborundum is another name of –
Answer
Silicon carbide
655) Number of neutrons in an atom of hydrogen is -
Answer
Zero
656) Peroxyacetyl nitrate is a –
Answer
Secondary pollutant
657) The term 'brown air' is used for –
Answer
Photochemical smog
658) Soldering of two metals is possible because of the property of –
Answer
Cohesion
659) An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a –
Answer
Uninterrupted power supply (UPS)
660) Which method will be employed to test the hardness of water?
Answer
Formation of lather with soap
661) J.J. Thomson’s proposed model of action is generally called model.
Answer
Plum and pudding
662) Even after sunset, the air near the Earth's surface continue to receive heat due to –
Answer
Terrestrial Radiation
663) Trinitrotoluene is –
Answer
used as an explosive
664) The high reactivity of fluorine is due to -
Answer
its high electro negativity
665) is used for making vinegar.
Answer
Acetic acid
666) Major portion of the earth's crust is mainly constituted by –
Answer
Oxygen and Silicon
667) Cinnabar is an ore/mineral of –
Answer
Mercu
668) Human nails are made up of -
Answer
Keratin
669) Meson particles are found in-
Answer
Cosmic rays
670) Nitric acid does not react with -
Answer
Gold
671) The process of dissolving an acid or a base in water is a highly -
Answer
Exothermic reaction
672) Atomic number is equal to -
Answer
Number of protons
673) The gas dissolved in water that makes it basic is –
Answer
sulphur dioxide
674) The number of hydrogen bonds between guanine and cytosine in DNA is –
Answer
3
675) What happens when a drop of glycerol is added to crushed KMnO4 spread on a paper?
Answer
There is a violent explosion
676) Most commonly used bleaching agent is –
Answer
Chlorine
677) The heat value of combustion of Gasoline is -
Answer
47000 kJ/kg
678) Who developed the model of atomic structure?
Answer
Bohr and Rutherford
679) What is a common name for the substance which irritates lachrymal glands?
Answer
Tear Gas
680) Diamond is the form of carbon that is -
Answer
Crystalline
681) Inert gases are -
Answer
Chemically uncreative
682) The metallic constituents of hard water are -
Answer
Calcium, magnesium and iron
683) Ruby and sapphire are oxides of -
Answer
aluminium
684) Water has maximum density at –
Answer
4°C
685) gives hardness to stainless steel.
Answer
Carbon
686) The ‘solid waste’ is also known as -
Answer
Sludge
687) Chemical name of vinegar is -
Answer
Acetic acid
688) Mercury is a –
Answer
liquid metal
689) Spirit in contact with body gives cool sensation because it is –
Answer
highly volatile
690) Natural rubber is the polymer of :
Answer
Isoprene
691) In addition to hydrogen, the other abundant element present on Sun’s surface is -
Answer
Helium
692) If lime water is kept in the air, it turns milky due to presence of –
Answer
Carbondioxide
693) Heavy metal pollution of water is caused by:
Answer
Paints
694) Nitrogen forms a variety of compounds in all oxidation states ranging from -
Answer
-3 to + 5
695) The next higher homologue of C6H14 is -
Answer
C7H16
696) Biogas majorly contains -
Answer
Methane
697) The sewage obtained from water closets and urinals is known as –
Answer
Sanitary waste
698) In organic compounds, nitrogen is estimated by –
Answer
Dumas' method
699) The hottest part of the gas flame is known as –
Answer
luminous zone
700) What is dry ice?
Answer
Solid Carbon dioxide
701) Nail polish remover contains?
Answer
petroleum ether
702) Threshold limit value of copper in the atmospheric air is -
Answer
1.0 mg/m3
703) Silicone is a polymer of –
Answer
Dialkyl dichloro silane
704) Which is not an anasthetic agent in surgical operations?
Answer
Acetone
705) Brass is an alloy of :
Answer
Cu and Zn
706) Iron is prevented from rusting by coating with zinc. This process is called as –
Answer
Galvanisation
707) Chemical that is used in photography -
Answer
Silver bromide
708) The nuclear reaction in which a heavy nucleus splits into two nuclei of nearly equal mass is called -
Answer
Nuclear fission
709) Sodium Carbonate is commonly known as -
Answer
Washing Soda
710) When a bond is formed between two atoms, the energy of the sys-tem will –
Answer
remain the same
711) The ore of Aluminium is -
Answer
Bauxite
712) lodex, a pain relief balm, has the smell of _.
Answer
Methyl salicylate
713) A complex compound in which the oxidation number of a metal is zero is -
Answer
[Ni (CO)4]
714) What is a Bakelite?
Answer
Polymer
715) What do you understand by the term Espuma?
Answer
Foam
716) The element used for vulcanizing rubber is -
Answer
Sulphur
717) Heavy metals got their name because compared to other atoms they have -
Answer
Higher atomic masses
718) Concentration of a material which is lethal to 50% animal is called–
Answer
LD50
719) Muddy water is treated with alum in purification process, it is termed as :
Answer
coagulation
720) ‘Plaster of pans’ chemically known as -
Answer
Calcium sulphate
721) Which mineral is the ore of aluminium?
Answer
Bauxite
722) Which gas is used for converting vegetable oils into saturated fats?
Answer
H2
723) An electric iron has a heating element made of –
Answer
Nichrome
724) The process of covering water pipes made of Iron with Zinc layer to prevent corrosion is called –
Answer
Galvanization
725) Philosopher’s wool is chemically -
Answer
Zinc oxide
726) Charcoal is used in water treatment as a/an -
Answer
adsorbent
727) The chemical used for cloud seeding for artificial rains is -
Answer
Silver Iodide
728) The percentage of oxygen in air is approximately –
Answer
0.21
729) What is the second largest cornponent in milk?
Answer
Fat
730) The presence of Cobalt in Vitamin B12 was established for the first time by –
Answer
Spectroscopy
731) Coating of solid waste with impervious material is known as –
Answer
Encapsulation
732) Sweat contains water and .
Answer
Salt
733) How many bones are there in a newly born infant?
Answer
280
734) White phosphorus is generally kept under –
Answer
Water
735) Brass contains –
Answer
Copper and Zinc
736) Which is the purest commercial form of iron?
Answer
Wrought iron
737) Ultra purification of a metal is done by –
Answer
zone melting
738) An antiknock for petrol is -
Answer
lead tetraethyl
739) The ratio of Pure gold and 18 carot gold is –
Answer
0.75
740) Limestone is a raw material used by which industry?
Answer
Cement
741) The compound used in prickly-heat powder to prevent excessive sweating is –
Answer
Boric acid
742) The colour of Emerald is -
Answer
Deep Green
743) The oxygen liberated during Photosynthes is comes from -
Answer
Water
744) Permanent hardness of water, due to sulphates of the metal, can be destroyed by the use of -
Answer
Zeolites
745) Adding which substance gives blue colour to glass?
Answer
Cobalt oxide
746) The antiparticle of an electron is –
Answer
Positron
747) Vinegar is .
Answer
diluted acetic acid
748) What is the product formed when sodium bicarbonate is heated strongly?
Answer
Sodium Carbonate
749) Atomic size refers to the of an atom.
Answer
Radius
750) Which is the highest quality of hard coal?
Answer
Anthracite
751) The soft silvery metalic element which ionizes easily when heated or exposed to light and is present in atomic clocks is –
Answer
Cesium
752) Catalytic converters are generally made from –
Answer
Transition metals
753) In galvanization, iron is coated with –
Answer
Zinc
754) Which one of the folling is also khow as solution?
Answer
Ahomogeneous mixture
755) The chief source of naphthalene is -
Answer
Coal-tar
756) This substance is commonly known as alcohol and is also used in medicines such as tincture iodine, cough syrups, and many tonics. This is -
Answer
Ethanol
757) Enzymes are -
Answer
Proteins
758) Sulphuric acid is –
Answer
dibasic
759) When Arsenic atoms are added Germanium lattice, it becomes a/an -
Answer
Extrinsic semiconductor
760) Hydrogen bomb is based upon the principle of .
Answer
Nuclear fusion
761) In an acid base reaction which product is produced along with a salt?
Answer
Water
762) The element present in the largest amount in rocks and minerals is -
Answer
silicon
763) Washing soda is -
Answer
sodiun carbonate
764) An element that does not occur in nature but can be produced artificially is –
Answer
plutonium
765) Chloroform can be used as –
Answer
Anaesthetic
766) Gas released during Bhopal tragedy was –
Answer
Methyl isothiocyanate
767) When water itself combines chemically with some element or mineral it is called –
Answer
Hydration
768) The electronic configuration of an atom having atomic number `20' is –
Answer
2, 8, 8, 2
769) Which chemical is used to ripen mangoes artificially?
Answer
Calcium Carbide
770) 'Monazite' is an ore of -
Answer
Thorium
771) The luster of a metal is due to -
Answer
presence of free electrons
772) The depletion of Ozone layer is mainly due to –
Answer
Chlorofluorocarbons
773) Glass is soluble in -
Answer
HF
774) Acid rain is caused by -
Answer
SO2 and NO2
775) What happens in a reduction reaction?
Answer
addition of Hydrogen
776) The energy released at the end of digestion is in the form of:
Answer
chemical energy
777) The fuel in atomic pile is -
Answer
uranium
778) The gas used for artificial ripening of green fruit is -
Answer
Ethylene
779) A mixture of water and alcohol can be separated by –
Answer
Distillation
780) The inert gas abundantly found in widely distributed is -
Answer
Ar
781) Brine refers to :
Answer
Salt water
782) The Bhopal tragedy was caused by the gas -
Answer
methyl isocyanate
783) The gas that usually causes explosions in coal mines is -
Answer
Methane
784) The chemical name for common salt -
Answer
Sodium chloride
785) The I.C Chip used in a computer is made up of -
Answer
Silicon
786) The chemical name of "Plaster of Paris" commonly used for setting broken bones is –
Answer
Calcium sulphate
787) The element found in the surface of the Moon is –
Answer
Titanium
788) Gypsum is used for improvement of:
Answer
Saline soils
789) Spontaneous change is one in there is:
Answer
A lowering of free energy
790) In a freezer ice cubes will be formed more quickly in trays made of -
Answer
aluminium
791) Who discovered X-rays?
Answer
W. C. Roentgen
792) The important metal used with iron to produce stainless steel is –
Answer
Chromium
793) Ozone layer in the upper parts of the atmosphere serves as a protective shield against harmful
Answer
solar ultraviolet radiation
794) The two metal ions that cause hardness to water are:
Answer
Calcium, Magnesium
795) The liquid waste from kitchens and baths, of residences is known as:
Answer
Sullage
796) Quartz is made of –
Answer
Sodium Silicate
797) Exposure to mixtures of chemicals are greater than expected on the basis of effects of expo-sure to each chemical individually. This is known as –
Answer
Synergism
798) The filter over which sewage is sprinkled is called as –
Answer
Trickling filter
799) Milk of magnesia is a suspension of –
Answer
magnesium hydroxide
800) Iodine value is used to estimate –
Answer
Unsaturation in oil
801) Element 106 was discovered by –
Answer
Seaborg
802) Milk of magnesia is an example of a/an -
Answer
Base
803) A bee-sting leaves an acid which causes pain and irritation. The injected acid is -
Answer
methanoic acid
804) Earth's atmosphere is an envelope of gases extending to a height of –
Answer
200 km
805) In its reaction with silver nitrate, C2H2 shows –
Answer
Acidic property
806) Iron is extracted from -
Answer
Haematite
807) Wood spirit is –
Answer
Methyl alcohol
808) Liquid metal is -
Answer
Mercury
809) The fat of a common mussel-secretes a sticky glue that can be used to make heart implants. The unique chemical compound present in the glue is:
Answer
Dihydroxy phenyl alanine
810) Nitrogen is an essential constituent of all:
Answer
Proteins
811) Ferrous sulphate is used in water treatment as a/an -
Answer
Coagulant aid
812) Philosopher's Wool is -
Answer
Zinc oxide
813) The process by which milk is converted to curd is called –
Answer
Fermentation
814) The technique of calculating the age of fossil organisms is -
Answer
Radiocarbon dating
815) "Fire-fighting clothes" are made from –
Answer
Asbestos
816) Hydrofluoric acid is not kept in glass bottles because it reacts with -
Answer
silicon dioxide of glass
817) ‘Freon' used as refrigerants is chemically known as -
Answer
chlorofluoro hydrocarbon
818) One light year is equal to -
Answer
9.46x 10¹⁵m
819) Which gas is used in fire extinguishers?
Answer
Carbon dioxide
820) Combustion of a candle is a/an -
Answer
exothermic reaction
821) Another name for baking soda is :
Answer
Sodium bicarbonate
822) Who invented the modern Periodic table?
Answer
Mendeleev
823) Brass is an alloy of -
Answer
Zinc and Copper
824) "Bhopal gas tragedy" 1984 is related to –
Answer
Methyl isocyanate
825) The percentage of nitrogen present in ammonium sulphate is –
Answer
0.27
826) Surface water is a better source of drinking water because it is poor in -
Answer
Arsenic
827) Saturated hydrocarbons are called -
Answer
Alkanes
828) Which type of fire extinguisher is used for petroleum fire?
Answer
Foam type
829) The function of skimming tank in sewage treatment is to remove –
Answer
oil and fatty substances
830) Who discovered Oxygen?
Answer
Carl Scheele
831) The element with highest first ionization energy is -
Answer
helium
832) The chief source of naphthalene is –
Answer
Coal-tear
833) KMnO4 can be used as a/an -
Answer
disinfectant
834) Seaweeds are important source of –
Answer
iodine
835) The resources which can be used continuously, year-after-year are called –
Answer
Renewable
836) Match sticks are made of -
Answer
Red phosphorus
837) Newlands' table, the elements were placed with the halogens -
Answer
Co and Ni
838) Iron rusts quickly in –
Answer
Sea water
839) Aerated water contains –
Answer
CO2
840) In electro-refining, the pure metal is deposited on –
Answer
cathode
841) Natural rubber is a polymer of –
Answer
Isoprene
842) The effect or response produced by two or more chemicals are less than the sum of the effects or response that the chemical would produce individually is known as -
Answer
Antagonism
843) The chemical formula of the laughing gas is –
Answer
N2O
844) Radioactive elements emit –
Answer
α, β and γ radiations
845) The chemical substance present in bones and teeth is -
Answer
Calcium phosphate
846) The percentage of carbon in cost iron is :
Answer
3 to 5
847) The compound that has the least value for octane number is –
Answer
n-heptane
848) The gas causing acid rain in an industrial area is -
Answer
Sulphur dioxide
849) A colloidal system in which a liquid is dispersed in a liquid is called –
Answer
emulsion
850) When a lead storage battery is discharged -
Answer
Sulphuric acid is consumed
851) Chemically fats and oils are:
Answer
Triesters
852) Washing soda is the common name of-
Answer
Sodium Carbonate
853) Maximum permissible concentration of copper in drinking water in mg/L, is –
Answer
1
854) Oxygen has (+) oxidation number only in –
Answer
OF2
855) Select the one which is not a mixture –
Answer
Distilled water
856) When Hydrogen starts burning in air, it produces?
Answer
Water
857) Carbon occurs in nature in the purest form as -
Answer
Diamond
858) In an oxygen molecule, two atoms are united by -
Answer
two bonds
859) The inert gas which is substituted for nitrogen in the air used by deep sea divers for breathing is –
Answer
Helium
860) Rectified spirit is :
Answer
95% ethyl alcohol
861) Nylon is made up of :
Answer
Polyamide
862) Which is a natural colloid?
Answer
Blood
863) Stilton is a –
Answer
Semiconductor
864) The orientation of an atomic orbital is governed by –
Answer
magnetic quantum number
865) Maximum permissible concentration of total hardness in drinking water is –
Answer
200
866) Electric fuse is an alloy of –
Answer
tin and lead
867) Ozone layer is present in -
Answer
Stratosphere
868) Taj Mahal is greatly affected due to –
Answer
Acid rain
869) The most abundant constituent of atmospheric air is –
Answer
nitrogen
870) In the periodic table of elements, on moving from left to right across a period, the atomic radius –
Answer
decreases
871) The wire of flash bulbs is made up of –
Answer
Mg
872) Radiations which is not emitted during radioactivity is –
Answer
Cathode rays
873) Citric acid is present in free form in –
Answer
Lemon
874) Ultraviolet rays can be used in water treatment as –
Answer
Disinfectant
875) The heaviest naturally occurring element is:
Answer
Uranium
876) Vinegar is used as a condiment, and in the pickling of vegetables and other foods. What is the constituent of vinegar?
Answer
Ethanoic acid
877) The inert gas which is substituted for nitrogen in the air used by deep sea divers for Breathing is:
Answer
Helium
878) Asbestos is formed of :
Answer
Calcium and Magnesium
879) Energy posses by a body in motion is called -
Answer
Kinetic Energy
880) Natural rubber is a polymer derived from?
Answer
isoprene
881) The value of Avogadro Number is -
Answer
6.023 x 1023
882) In silvery paints, the main constituent present is -
Answer
Aluminium powder
883) The gas involved in Bhopal incident was -
Answer
Methyl isocyanide
884) Alcohol prepared by the distillation of wood is:
Answer
Methyl alcohol
885) The metal that is used as a catalyst in the hydrogenation of oils is -
Answer
Ni
886) The particle required to continue the chain process of Uranium fission is –
Answer
Neutron
887) Chemical name of bleaching powder is –
Answer
Calcium hypochlorite
888) Alcoholic OH) group can be identified by :
Answer
FeCl3 Test
889) When ice cubes are made, the entropy of water –
Answer
decreases
890) In arc welding, Argon is used because of its -
Answer
Low reactivity with metal
891) Superconductivity is a material property associated with -
Answer
a loss of thermal resistance
892) What role does enzyme pepsin play?
Answer
It converts proteins into peptones
893) Water gas is the mixture of –
Answer
carbon monoxide and hydrogen
894) Hardness of the water is commonly measured in terms of -
Answer
Calcium carbonate equivalents
895) One property of ammonia is –
Answer
Its aqueous solution turns red litmus blue
896) ‘Aerosol’ is -
Answer
Suspended solid particles in air
897) Bridgmanite is –
Answer
Earth's most abundant mineral
898) The molecular mass of a has is –
Answer
twice its vapour pressure
899) Thermal electricity is generated by using which of these?
Answer
Coal, Natural Gas and Petroleum
900) The mass number of a nucleus is –
Answer
sometimes more - and somtimes equal to its atomic number
901) Ionisation energy of nitrogen is greater than that of oxygen because nitrogen has –
Answer
stable half filled 2p sub level
902) Graphite is used in nuclear reactors for-
Answer
reducing the speed of fast neutrons
903) Bleaching powder is prepared by passing –
Answer
Chlorine over slaked lime
904) Acid rain is caused due to pollution of atmosphere by –
Answer
oxides of nitrogen and sulphur
905) The working of a dry cell is based on -
Answer
Electrolysis
906) Potassium Permanganate is used for purifying drinking water, because .
Answer
It is an oxidising agent
907) Oxide of sulphur present in the atmosphere are washed down by rains to cause –
Answer
Depletion of fossil fuel reserves
908) An emulsifier is an agent which –
Answer
stabilises an emulsion
909) Hydrogen is not found in atmosphere because –
Answer
it is the lightest gas
910) The mass number of a nucleus is -
Answer
the sum of the number of protons and neutrons present in the nucleus
911) What are transition elements?
Answer
Elements whose two outermost shells are incomplete
912) A balloon filled with helium rises in air because –
Answer
helium is less dense than air
913) Aqua regia is a 1 : 3 mixture, by volume, of –
Answer
conc, nitric acid and conc. hydrochloric acid
914) The freezer in a refrigerator is fitted near the top –
Answer
it facilitates convection currents
915) What happens when a chemical bond is formed?
Answer
energy is always absorbed
916) Silver nitrate solution is kept in brown bottles in laboratory because -
Answer
brown bottles stops the passage of light through it
917) In upper layer of atmosphere ozone is formed by -
Answer
the action of ultraviolet rays on oxygen
918) Water is not effective in extinguishing a fire caused by petrol because –
Answer
water and petrol are immiscible with each other and petrol which forms the upper layer continues to burn
919) "Ail the four quantum numbers of two electrons in an atom are not the same." It is the law of —
Answer
Exclusion Principle of Pauli
920) The three elements most needed in common fertilizers are –
Answer
Nitrogen, Phosphorous and Sodium
921) Metal are good conductors, because –
Answer
they contain free electrons
922) Helium gas is filled in ballons because -
Answer
it is lighter than air
923) Ammonial is a mixture of –
Answer
aluminium powder and ammonium nitrate
924) Gelatin is mostly used in making icecreams in order to -
Answer
stabilise the colloid and prevent crystallisation
925) Glycol is added to aviation gasoline because it -
Answer
prevents freezing of petrol
926) Rust is -
Answer
A mixture of Fe₂O₃, 3H₂O and FeO
927) Catalyst is a substance which –
Answer
None of these
928) Table salt gets moist during rainy season because –
Answer
sodium chloride contains hygroscopic impurities like magnesium chloride
929) The BOD values of water indicate the –
Answer
amount of oxygen used for biochemical oxidation
930) The addition of gypsum to port-land cement helps in :
Answer
preventing rapid setting of cement
931) Milk is a colloidal system in which:
Answer
Fat is dispersed in water
932) The presence of ozone in the stratosphere is responsible for –
Answer
checking the penetration of ultra-violet rays to the earth
933) The advantage of detergents over soaps is –
Answer
Detergents give lather even with hard water
934) Cement is usually a mixture of –
Answer
Calcium silicate and calcium alurninate
935) Milk is a colloidal system in which:
Answer
Fat is dispersed in water
936) The presence of ozone in the stratosphere is responsible for –
Answer
checking the penetration of ultra-violet rays to the earth
937) The advantage of detergents over soaps is –
Answer
Detergents give lather even with hard water
938) What is the objective of the 'Kyoto Protocol'?
Answer
To reduce greenhouse gases
939) The lustre of the metals is because of –
Answer
reflection of light due to the presence of free electrons
940) Cloud is a colloidal dispersion of –
Answer
Water drops in a dispersion medium of air
941) Conduction band electrons have more mobility than holes because they –
Answer
experience collision less frequently
942) Carbon dioxide is called a greenhouse gas because -
Answer
it absorbs infrared radiation
943) Sullage water is –
Answer
waste water released from kitchen
944) A solution is -
Answer
a homogeneous mixture of two or more substances
945) Choose the incorrect statement pertaining to organic compounds -
Answer
They are not easily combustible
946) Which of the process is known as nitrification?
Answer
Conversion of ammonia to nitrites
947) Acid rain is caused due to pollution of atmosphere by –
Answer
oxides of nitrogen and sulphur
948) Neuron is -
Answer
Fundamental unit of nervous system
949) Water cycle refers to –
Answer
constant movement of water from ocean to land and back to ocean once again
950) When a spoon is to be electroplated with nickel the spoon is -
Answer
made cathode and a pure nickel red, the anode
951) The mass number of a nucleus is -
Answer
the sum of the number of protons and neutrons present in the nucleus
952) Helium is added to the oxygen supply of deep sea divers because it is -
Answer
less soluble in blood than nitrogen at high pressure
953) The chemical bahaviour of an atom depends upon -
Answer
the number of electrons orbiting around the nucleus
954) Methyl phenyl ether can be obtained by reacting -
Answer
phenolate ions and methyl iodide
955) Acid Rain is caused due to pollution of atmosphere by –
Answer
Oxides of nitrogen and sulphur
956) Air is said to be saturated when -
Answer
it contains maximum content of water vapour
957) Methanol cannot be dried with anhydrous CaCl2 because -
Answer
it forms a solid CaCl2 × 4CH3OH
958) Acid rain is caused by the pollution of environment by –
Answer
Nitrous oxide and Sulphur dioxide
959) What are the components responsible for acid rain?
Answer
Sulphur dioxide (SO2) and Nitrogen oxides (NOx)
960) Thermal electricity is generated by using which of these?
Answer
Coal, Natural Gas and Petroleum
961) Synthetic detergents are made from –
Answer
Sodium salt of benzene sulphonic acid
962) The open "Sigrees” or coal stoves often require fanning to sustain burning because of -
Answer
tendency of carbon dioxide to form a layer along with dust smoke
963) Antacid tablets consist of –
Answer
Hydroxides of magnesium and aluminium
964) Acid rain is caused by the pollution of environment by -
Answer
nitrous oxide and sulphur dioxide
965) Synthetic detergents are prepared from –
Answer
hydrocarbons of petroleum
966) Metals have .
Answer
High melting and boiling point
967) Soap helps in better cleaning of clothes because -
Answer
It reduces the surface tension of solution
968) Acid rain is caused by, the pollution of environment by -
Answer
carbon dioxide and nitrogen
969) The enormous amount of energy released in an explosion of an atomic bomb is due to the -
Answer
conversion of neutrons into protons
970) Organic food is supposed to be better for human consumption because –
Answer
It is grown without the use of chemicals & synthetic pesticides
971) Nitrogen fixation is a process of -
Answer
Conversion of molecular nitrogen to ammonia
972) What are soaps?
Answer
Sodium or potassium salts of heavier fatty acids
973) Electrolysis of an aqueous solution of copper sulphate using copper electrodes gives -
Answer
Copper at eathode and oxygen at anode.
974) Phosphorus is kept in water because –
Answer
its ignition temperature is very low
975) The relation between bond length and bond energy is -
Answer
Higher the bond energy, shorter the bond length
976) In an atomic explosion enormous energy is released which is due to the -
Answer
Conversion of mass into energy
977) Sea water is saltier than rain water because –
Answer
Rivers wash away salts from earth and pour them into the sea
978) Refrigerators keep food unspoiled because –
Answer
at its low temperature, bacteria and moulds are inactive
979) Why is water not suitable for putting out a petrol fire?
Answer
Water, being heavy, slips below petrol which thus remains in contact with air and burns
980) All isotopes of the same element have _.
Answer
the same atomic number but different atomic masses
981) Sodium vapour lamps glow with yellow colour. This is due to -
Answer
the emission of excess energy absorbed by sodium atoms, in the yellow region of the spectrum
982) Photo chemical smog is a resultant of the reaction among –
Answer
NO2, O3 and peroxy acetyl nitrate in the presence of Sunlight
983) During the formation of a chemical bond -
Answer
energy decreases
984) Cyanide poisoning causes death in seconds because -
Answer
It causes cardiac arrest
985) Why is water not suitable for putting out a petrol fire?
Answer
Water, being heavy, slips below petrol which thus remains in contact with air and burns
986) Iron and manganese present as pollutants in water cannot be re-moved by -
Answer
chlorination
987) What are isobars?
Answer
Elements with different atomic number but same mass number
988) Sulphur dioxide level in the atmosphere can be reduced by using -
Answer
low - sulphur fuels
989) Chlorine atom and chloride ions -
Answer
Have an equal number of protons
990) An atom of an element with mass number 23 and atomic number 11 will have-
Answer
11 protons, 12 neutrons and 11 electrons
991) Atoms of different elements have -
Answer
different atomic number and different number of valence electrons
992) The molecular mass of a has is –
Answer
twice its vapour pressure