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SSC CGL MCQ : Chemistry

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1. The most abundant elements is:

(a) Silicon

(b) Calcium

(c) Nitrogen

(d) Oxygen

2. Bar is a unit of

(a) pressure

(b) force

(c) energy

(d) frequency

3. Oxygen and ozone are –

(a) allotropes

(b) isomers

(c) isotopes

(d) isobars

4. Who among the following proposed that atom is indivisible?

(a) Dalton

(b) Berzelius

(c) Rutherford

(d) Avogadro

5. Neutron was discovered by

(a) J. J. Thomson

(b) Chadwick

(c) Rutherford

(d) Priestley

6. The word ‘insolation’ means

(a) Matters which insulates

(b) Incoming solar radiation

(c) Insoluble matters

(d) None of the above

7. Neutrino has-

(a) charge + 1, mass 1

(b) charge 0, mass 0

(c) charge – 1, mass 1

(d) charge 0, mass 1

8. Indicate the correct arrangement for electromagnetic radiation in order of their increasing wavelength-

(a) Visible, infrared, microwave, Xrays

(b) X – rays, infrared, visible, microwave

(c) Microwave, infrared, visible, X – rays

(d) X- rays, visible, infrared, microwave

9. The photoelectric effect is described as the ejection of electrons from the surface of metal when-

(a) it is used

(b) it is placed in strong electrick field

(c) electrons of suitable velocity impinge on it

(d) Light of suitable wavelength falls on it

10. Which electro magnetic radiation is emitted by radioactive substance-

(a) Y– rays

(b) Radio waves

(c) Micro waves

(d) x – ray

11. Species containing same number of electrons are called:

(a) Isotopes

(b) Isobars

(c) Isoelectronic

(d) Isotones

12. Isobars are lines displaying areas of equal-

(a) Humidity

(b) Temperature

(c) Rainfall

(d) Atmospheric pressure

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13. The phenomenon of radioactivity was discovered in 1898 A. D. by-

(a) Henri Becquerel

(b) J.J Thomson

(c)`Marie Curie

(d) Pierre Curie

14. The α – particles are-

(a) High energy electrons

(b) Positively charged hydrogen ions

(c) High energy x –ray radiations

(d) double positively charged helium nuclei

15. Heavy water is used as a coolant in nuclear reactors Heavy water is

(a) Water rich in minerals

(b) Ozonized water

(c) Water containing minerals of heavy metal

(d) Water containg heavy isotope of hydrogen

16. Gamam rays are-

(a) high energy electrons

(b) low energy electrons

(c) high energy electromagnetic

(d) high energy positions waves

17. Neclear fission is caused by the impact of –

(a) Neutrons

(b) Protons

(c) Deuteron

(d) Electron

18. Hydrogen bomb is based on the principle of –

(a) nuclear fission

(b) nuclear fusion

(c) natural radioactivity

(d) artificial radioactivity

19. In nuclear raeactors the speed of neutrons is slowed down by –

(a) heavy water

(b) ordinary water

(c) zinc rods

(d) moten caustic soda

20. In treatement of cancer, which of the following is used-

(a)131_I53

(b)32_P15

(c) 60_CO27

(d) 2_H1

21. What was the fissionable material used in the bombs dropped at Nagasaki (Japan) in the years 1945?

(a) Sodium

(b) Potassium

(c) Plutonium

(d) Uranium

22. ‘Yellow cake’ an item of smuggling across broder is-

(a) a crude form of heroin

(b) a crude form of cocaine

(c) uranium oxide

(d) unrefined gold

23. Cobalt – 60 is commonly used in radiation therapy because it emits-

(a) α – rays

(b) beta rays

(c) Gamma ray

(d) X – rays

24. H2O is liquid and H2S is a gas because-

(a) Oxygen forms stronger hydrogen bond than sulphur

(b) Oxygen is less electronegative than sulphur

(c) Atomic radius of oxygen is less than that of sulphur

(d) Atomic radius of oxygen is greater than that of sulphur

25. The acid used in eye wash is

(a) Oxalic acid

(b) nitric acid

(c) Boric acid

(d) None

26. Source of vitamin C is

(a) Nitric acid

(b) Ascorbic acid

(c) Oxalic acid

(d) Maleic acid

27. Hydrochloric acid is also known as

(a) Garlic acid

(b) Picric acid

(c) Muriatic acid

(d) Chloric acid

28. Aqua Regia contains

(a) 3 parts of conc. HCI + 1 part of con. HNO3

(b) 3 parts of conc. HCI + 1 part of con. H2SO4

(c) 3 parts of conc. H2SO4 + 1 part of con. HNO3

(d) None of these

29. Rate of diffusion of a gas is –

(a) Directly proportional to its density

(b) Directly proportional to its molecular mass 

(c) Directly proportional to the square of its molecular mass

(d) Inversely propostional to the square root of its molecular mass

30. Deviations from ideal behavior will be more of the gas issubjected to-

(a) Low temperature and high pressure

(b) High temperature and low pressure

(c) Low temperature

(d) High temperature

31. An ideal gas is one which obeys-

(a) Gas laws

(b) Boyle’s laws

(c) Charle’s law

(d) Avogadro’s law

32. Alcoholic fermentation is brought about the action of –

(a) yeast

(b) CO2

(c) O2

(d) CO

33. The enzymes are killed-

(a) At a very high temperature

(b) During chemical reaction

(c) At low temperature

(d) Under atmospheric pressure

34. If a refrigerator’s door is kept open, then-

(a) Room will be cooled

(b) Room will be heated

(c) May get cooled or heated depending upon the weather

(d) No effect on room

35. When a gas is subjected to adiabatic expansion, it gets cooled due to-

(a) No chage in tntropy

(b) Loss in kinetic energy

(c) Decreases in velocity

(d) Energy spent in doing work

36. Coal gas is a mixure of-

(a) H2, CH4, CO

(b) H2, N2, CO

(c) H2, N2, O2

(d) H2, O2, CO2

37. The gas supplied in cylinders for cooking is-

(a) marsh gas

(b) LPG

(c) Mixture of CH4 and C2H6

(d) Mixture of ethane and propane

38. The most electronegative element among the following is-

(a) Chlorine

(b) Oxygen

(c) Fluorine

(d) Sodium

39. When a gas is turned into a liquid, the process is called-

(a) Condensation

(b) Evaporation

(c) Deposition

(d) Sublimation

40. The boiling point of water decreases at higher altitudes is due to

(a) Low temperature

(b) Low atmospheric pressure

(c) High temperature

(d) High atmospheric pressure

41. At high altitudes the boiling point of water lowers because-

(a) Atmoshperic pressure is low

(b) Atmospheric pressure is high

(c) Temperature is low

(d) None of these

42. In electro – refining, the pure metal is deposited on-

(a) Cathode

(b) Anode

(c) Vessel

(d) Electrolyte

43. In galvanization, iron is coated with

(a) Copper

(b) Zinc

(c) Tin

(d) Nickel

44. Smoke is a colloidal dispersion of a–

(a) Solid in a gas

(b) Liquid in a gas

(c) Gas in a solid

(d) Gas in a gas

45. When a few typical solutes are separted by aparticular selective membrane, such as protein particles from blood corpuscles, the process is called-

(a) Exosmosis

(b) Dialysis

(c) Transpiration

(d) Endosmosis

46. The bleeding of a wound is stopped by the application of ferric chloride because-

(a) Blood starts flowing in the opposite direction

(b) Ferric chloride seals the blood vessels

(c) Blood reacts and a solid is formed which seals the blood vessels

(d) Blood is coagulated and the blood vessels are sealed

47. Cod liver is an example of –

(a) Oil emulsion

(b) Oil in water emulsion

(c) Water in oil emulsion

(d) Water in water emulsion

48. Milk is an example of –

(a) oil in water emulsion

(b) Water in oil emulsion

(c) Fat in oil emulsion

(d) Fat in water emulsion

49. The blue colour of water in the sea is due to-

(a) Refraction of the blue light by the impurities in sea water

(b) Scattering of blue light by water molecules

(c) Refraction of blue sky by sea water

(d) Absorption of other colours except the blue colour by water molecules

50. Which one is an example of Miscelles System here-

(a) Soap – Water

(b) Protein + Water

(c) Rubber – Benzene

(d) All of these

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