General Chemistry MCQ Solved Paper for UPSC CDS

1. The addition of a neutron to the nucleus of an atom
A. increases the atomic mass of the atom
B. decreases the atomic mass of the atom
C. increases the charge on the nucleus
D. decreases the charge on the nucleus
Answer : A

2. On chemical analysis, a bottle cork is found to contain primarily
A. proteins
B. carbohydrates
C. tannins
D. lipids
Answer : B

3. Beri-beri is caused by deficiency of Vitamin
A. A
B. C
C. B12
D. B1
Answer : D

4. The iron salt used in blue prints is
A. ferric sulphate
B. ferric oxalate
C. ferric nitrate
D. ferric chloride
Answer : B

5. Marsh gas is
A. ethane
B. ethylene
C. acetylene
D. methane
Answer : D

6. Biogas is obtained during
A. decomposition of petrol
B. fermentation of animal and plant waste
C. destructive distillation of coal
D. electrolysis of water
Answer : B

7. The rate of setting of cement is slowed down by the addition of
A. quicklime
B. gypsum
C. soda lime
D. bleaching powder
Answer : B

8. A light alloy having high tensile strength is
A. German silver
B. solder
C. magnalium
D. bell metal
Answer : C

9. Which of the following can absorb gases quickly?
A. Activated charcoal
B. Anthracite coal
C. Diamond
D. Graphite
Answer : A

10. Which one of the following is present in the largest amount in terms of per cent by mass in the earth's crust?
A. Silicon
B. Oxygen
C. Carbon
D. Calcium
Answer : B

11. According to the modern Periodic Law, the properties of elements are periodic functions of their
A. valency
B. atomic mass
C. number of neutrons
D. atomic number
Answer : D

12. Glass is a ______ mixture of metallic ______.
A. homogeneous, sulphates
B. heterogeneous, nitrates
C. heterogeneous, carbonates
D. homogeneous, silicates
Answer : D

13. In the mouth, starch is converted into ______ by the action of saliva.
A. sucrose
B. glucose
C. fructose
D. mannose
Answer : D

14. Which of the following is used as an illuminant?
A. Gasoline
B. Benzoline
C. Kerosene
D. Petroleum ether
Answer : C

15. The metal which reacts most violently with cold water is
A. calcium
B. sodium
C. magnesium
D. potassium
Answer : D

16. Nitrous oxide used as anaesthetic is usually mixed with
A. ethyl alcohol
B. chloroform
C. oxygen
D. methyl alcohol
Answer : C

17. Rusting is
A. an oxidation process
B. a reduction process
C. a physical change
D. an electro-chemical process
Answer : D

18. Which of the following statements regarding natural radioactivity is true?
A. It is spontaneous disintegration of atoms
B. It is induced by bombardment with projectiles
C. It is transmutation of atoms with projectiles
D. It is dependent on temperature
Answer : A

19. Which of the following is a mixture?
A. Baking soda
B. Milk
C. Chloroform
D. Copper wire
Answer : B

20. A metal which occurs 'free' in nature is
A. gold
B. zinc
C. tin
D. molybdenum
Answer : A

21. BHC is a
A. Rodenticide
B. Herbicide
C. Pesticide
D. Fungicide
Answer : C

22. The fertilizer which has the largest percentage of nitrogen is
A. urea
B. ammonium nitrate
C. ammonium sulphate
D. calcium cyanamide
Answer : A

23. The discoverer of chloroform was
A. Liebig
B. Pasteur
C. Bunsen
D. Erlenmeyer
Answer : A

24. The function of nitrogen in air is
A. to make air a moderate supporter of combustion
B. to maintain the density of air constant
C. to prevent the hydrogen in air from exploding
D. to reduce the poisonous nature of ozone in air
Answer : A

25. During fermentation, the by-product is
A. ethyl alcohol
B. methyl alcohol
C. carbon monoxide
D. carbon dioxide
Answer : D

26. Which of the following la a very good supporter of combustion?
A. Carbon monoxide
B. Oxygen
C. Nitrogen
D. Hydrogen
Answer : B

27. Which among the following is a local anaesthetic?
A. Chloroform
B. Morphine
C. Streptomycin
D. Cocaine
Answer : D

28. A non-metal which is a good conductor or heat and electricity is
A. iodine
B. sulphur
C. graphite
D. phosphorus
Answer : C

29. Which of the following types of water gives lather easily with soap?
A. Hard water
B. Heavy water
C. Soft water
D. Both (a) and (b)
Answer : C

30. Iron is coated with zinc to prevent rusting. The process is called
A. annealing
B. tempering
C. calcining
D. galvanising
Answer : D

31. Ascorbic acid is the chemical name for
A. Vitamin B6
B. Vitamin C
C. Vitamin K
D. Vitamin D
Answer : B

32. Quick lime has the formula
A. CaO
B. Ca(OH)2
C. NaOH
D. Na2CO3
Answer : A

33. Metals are usually heavy. A light metal is
A. manganese
B. copper
C. potassium
D. plumbum
Answer : C

34. Ozone occurs in the upper layers of air in the atmosphere because
A. it is lighter than air
B. in the lower layers it becomes unstable
C. ultra-violet light is present only in the upper layers
D. it mixes freely with O2 in the upper layers
Answer : C

35. In addition to nitric acid, another acid which may render iron passive is
A. acetic acid
B. oxalic acid
C. chromic acid
D. citric acid
Answer : C

36. Which of the following is used as a food preservative?
A. phenol
B. washing soda
C. absolute alcohol
D. vinegar
Answer : D

37. Which one of the following is used for dry cleaning?
A. Kerosene oil
B. Diesel oil
C. Lubricating oil
D. Petroleum ether
Answer : D

38. The malarial parasite was discovered by
A. Sir Ronald Ross
B. Sir Francis Haig
C. Dr Jagadish Chandra Bose
D. Sir CV Raman
Answer : A

39. The oldest known organic compound is
A. urea
B. methane
C. acetic acid
D. benzene
Answer : C

40. Smelling salt contains
A. ammonium chloride
B. ammonium carbonate
C. ammonium sulphate
D. potassium nitrate
Answer : B

41. Isotopes differ in the number of
A. Protons
B. Neutrons
C. Electrons
D. Protons and electrons
Answer : B

42. Which of the following process involves removal of the elements of water?
A. Hydrolysis
B. Hydrogenation
C. Dehydration
D. Dehydrogenation
Answer : C

43. Washing soda is
A. sodium hydroxide
B. sodium carbonate
C. sodium bicarbonate
D. potassium chloride
Answer : B

44. A metal which exhibits allotropy is
A. cobalt
B. tin
C. manganese
D. platinum
Answer : B

45. Graphite la a good conductor of electricity because
A. it is an allotrope of carbon
B. it gives CO2 on heating
C. it contains free electrons
D. it is oxidised to graphitic acid
Answer : C

46. Penicillin was discovered by
A. Alexander Fleming
B. Sir JJ Thomson
C. Dr Nessler
D. Sir John Russel
Answer : A

47. The compound which is both an antiseptic and a disinfectant is
A. phenol
B. iodoform
C. bleaching powder
D. blue vitriol
Answer : A

48. Rayon la made from
A. cotton
B. wool
C. cellulose
D. silk
Answer : C

49. The poisonous nature of carbon monoxide is due to
A. cutting off supply of oxygen
B. it™s being converted into carbon dioxide
C. its combination with haemoglobin of blood
D. its blocking of vocal chords
Answer : C

50. The raw materials required for the manufacture of glass are
A. silica, sodium nitrate and soda ash
B. silica, limestone and sodium nitrate
C. silica, sodium oxide and limestone
D. silica, soda ash and limestone
Answer : D