chemistry notes for competitive exams pdf in english

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chemistry notes for competitive exams pdf in english

1 Q) Which of the following is the lightest metal?
(a) Mercury
(b) Silver
(c) Lithium
(d) Lead

2 Q) The most important ore of aluminium is
(a) bauxite
(b) calamine
(c) calcite
(d) galena

3 Q) The element present in the largest amount in rocks and minerals is
(a) carbon
(b) silicon
(c) hydrogen
(d) aluminium

4 Q) An alloy used in making heating elements for electric heating devices is
(a) solder
(b) alloy steel
(c) nichrome
(d) German Silver

5 Q) German silver is an alloy of
(a) copper, nickel and silver
(b) silver, copper and aluminium
(c) zinc, copper and nickel
(d) silver, zinc and copper

6 Q) Match the following : ABCD will correctly match with
A. Aluminium 1 Monazite
B. Uranium 2 Pitchblende
C. Thorium 3 Bauxite
D. Lead 4 Galena
5 Haematite
(a) 5 3 2 4
(b)3 2 4 1
(c) 3 2 1 4
(d)2 3 1 5

7 Q) Diamond is an allotropic form of
(a) silicon
(b)carbon
(c) sulphur
(d)germanium

8 Q) Air is a/an
(a) compound
(b) element
(c) mixture
(d) electrolyte

9 Q) Which of the following is the best conductor of electricity?
(a) Ordinary water
(b) Sea water
(c) Boiled water
(d) Distilled water

10 Q) Balloons are filled with
(a) helium
(b) oxygen
(c) nitrogen
(d) argon

11 Q) The charcoal used to decolourise raw sugar is
(a) animal charcoal
(b) sugar charcoal
(c) coconut charcoal
(d) wood charcoal

12 Q) The most abundant metal in the earth’s crust is
(a) zinc
(b) copper
(c) aluminium
(d) iron

13 Q) Production of chlorofluorocarbons (CFC/freon) gas which is proposed to be
banned in India, is used in which of the following domestic products ?
(a) Television
(b) Tubelight
(c) Cooking gas
(d) Refrigerator

14 Q) The gas used to extinguish fire, is
(a) neon
(b) nitrogen
(c) carbon dioxide
(d) carbon monoxide

15 Q) In which of the following activities silicon carbide (corundum) is used ?
(a) Making cement and glass
(b) Disinfecting water of ponds
(c) Making casts for statues
(d) Cutting very hard substances

16 Q) The element common to all acids is
(a) carbon
(b) hydrogen
(c) oxygen
(d) sulphur

17 Q) Gobar gas contains mainly
(a) methane
(b) carbon dioxide
(c) butane
(d) carbon monoxide

18 Q) The most malleable metal is
(a) Silver
(b) Gold
(c) Aluminium
(d) Sodium

19 Q) Tetraethyl lead is used as
(a) mosquito repellent
(b) painkiller
(c) fire extinguisher
(d) petrol additive

20 Q) Which of the following is used in beauty parlours for hair setting?
(a) Chlorine
(b) Sulphur
(c) Phosphorus
(d) Silicon

21 Q) Which one among the following is not a periodic property i.e., does not show
any trend on moving from one side to the other in the Periodic Table?
(a) Atomic size
(b) Radioactivity
(c) Valency
(d) Electromagnetically

22 Q) Which one of the following is used as an anti-freezer, which effectively
depresses the freezing point of water in an automobile?.
(a) Ethylene glycol
(b) Propanoic acid
(c) Glutamic acid
(d) Glycolic acid

23 Q) Aqua-regia used by alchemist to separate silver and gold is a mixture of
(a) concentrated HNO, and concentrated H2SO4
(b) concentrated HC1 and concentrated H2SO4
(c) concentrated HN03 and concentrated HCl
(d) dilute HN03 and dilute HCl

24 Q) “Metal used to make wires for safety fuses must have ”
(a) very low resistivity and high melting point
(b) high resistivity and low melting point
(c) low resistivity and low melting point
(d) high resistivity and high melting point

25 Q) Which of the following is not a natural polymer?
(a) Wool
(b) Silk
(c) Cotton
(d) Teflon

26 Q) The ultra pure metal is obtained by
(a) calcination
(b) sublimation
(c) zone refining
(d) None of these

27 Q) Which one among the following polymers is used to make personal armour
such as combat helmets, ballistic face masks, and ballistic vests?
(a) Teflon
(b) PVC
(c) Bakelite
(d) Kevlar

28 Q) Assertion (A) A buffer solution is a mixture of a strong acid and its conjugate base
or a strong base and its conjugate acid.
Reason (R) Buffer solutions keep the pH at a nearly constant value.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true

29 Q) Which of the following gases in the atmosphere is/are responsible for acid
rains?
I. Oxides of sulphur
II. Oxides of nitrogen
III. Oxides of carbon

Select the correct answer using the codes given below
(a) I and II
(b) I and III
(c) Only II
(d) All of these

30 Q) Match the Following
List l List II
(Elements) (Ores/Minerals)
A. Copper 1. Corundum, Bauxite
B. Iron 2. Malachite, Azurite
C. Lead 3. Galena, Lanarkite
D. Aluminium 4. Haematite,Limonite
(a) 2 4 3 1
(b) 2 3 4 1
(C) 4 3 1 2
(d) 4 1 3 2

31 Q) Vermicompost is a/an
(a) inorganic fertilizer
(b) toxic substance
(c) Organic bio fertilizer
(d) synthetic fertilizer

32 Q) Which one of the following is involved for desalination of sea water?
(a) Simple osmosis
(b) Reverse osmosis
(c) Use of sodium aluminium silicate as zeolite
(d) Use of ion selective electrode

33 Q) Soaps are important cleansing agent and this property is due to their
emulsifying action. How does soap enhance the cleansing action?
(a) It has a strong acidic character which can dissolve the dirt
(b) It rises the temperature of the reaction
(c) It breaks triple bond formed between dirt and cloth
(d) It has capacity to render more prolonged the mixing of oil and water

34 Q) The animal fats undergo ‘auto-oxidation’ under ordinary temperature which
gives the fats a rancid taste and odour. Which one of the following causes the
rancid taste and odour of the fats?
(a) Platinum
(b) Carbon monoxide
(c) Carbon dioxide
(d) Aldehydes

35 Q) “The pungent smell of garlic is due to ”
(a) phosphate compound
(b) nitrate compound
(c) sulphur compound
(d) chlorine compound

36 Q) Which one among the following statement about an atom is not correct?
(a) Atoms always combine to form molecule
(b) Atoms are the basic units from which molecules and ions are formed
(c) Atoms are always neutral in nature
(d) Atoms aggregate in large numbers to form the matter that we can see, feel and
touch

37 Q) “The light emitted by firefly is due to ”
(a) radioactive substance
(b) chemiluminiscence process
(c) a photoelectric process
(d) burning of phosphorus

38 Q) Which one among the following metals is used in fireworks to make a
brilliant white light?
(a) Sodium
(b) Magnesium
(c) Aluminium
(d) Silver

39 Q) “Consider the following statements.
I. In the titration between weak bases and strong acids, the indicator such
as methyl orange is commonly used.
II. In the titration between a weak acid and a strong base, the indicator
such as phenolphthalein is commonly used. Which of the statements
given above is/are correct?”
(a) Only I
(b) Only II
(c) Both I and II
(d) Neither I nor II

40 Q) Which one among the following polymers is used for making bullet-proof
material?
(a) Polyvinyl chloride
(b) Polystyrene
(c) Polyethylene
(d) Polyamide

41 Q) Which one of the following is the softest?
(a) Sodium
(b) Iron
(c) Aluminium
(d) Copper

42 Q) Ethanol mixed petrol is being sold in various states wef January 1, 2003. The
percentage of ethanol in petrol is
(a) 10%
(b) 7%
(c) 6%
(d) 5%

43 Q) A polymer which is used for making ropes and carpet fibres is
(a) polyacetylene
(b) polypropylene
(c) polyacrylonitrile
(d) PVC

44 Q) Which one among the following salts causes hardness to the water?
(a) Calcium bicarbonate
(b) Calcium carbonate
(c) Sodium sulphate
(d) Potassium chloride

45 Q) Which one among the following is the natural polymer?
(a) Nylon
(b) Teflon
(c) PVC
(d) Cellulose

46 Q) Vinegar is used as a condiment, and in the pickling of vegetables and other
foods. What is the constituent of vinegar?
(a)Butanoic acid
(b) Methanoic acid
(c) Ethanoic acid
(d) Hexanoic acid

47 Q) Which of the following pesticide is applied to the foundation of buildings to
prevent termites?
(a) Aldrin
(b)Malathion
(c) Atrazine
(d)Carbaryl

48 Q) “Consider the following substances.
I. Cadmium
II. Boron
III. Nickel
Which of the substances given above is/are used as controlling rod in nuclear
reactor? ”
(a) All of these
(b) I and II
(c) II and III
(d) Only II

49 Q) Liquid sodium is used for the heat transfer medium in some of nuclear
reactor because
(a) sodium has high rate of vapourisation
(b) sodium has low density and high viscosity
(c) sodium has high specific heat than the most liquid metals
(d) All of the above

50 Q) Which one of the following petroleum refinery products has the lowest
boiling point?
(a) Kerosene
(b) Gasoline
(c) Diesel
(d) Lubricating oil

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