Daily Chemistry Quiz for RRB NTPC : 17/05/2019

1) The formula of plaster of paris is

a) CaSO4

b) CaSO4H2O

*c) CaSO41/2H2O

d) CaSO42H2O

2) A white powder insoluble in water dissolves in ammonim hydroxide) It could be

*a) silver chloride

b) aluminium oxide

c) calcium carbonate

d) barium sulphate

3) Mass number of an element represents

*a) number of protons and neutrons

b) number of electrons and neutrons

c) number of protons and electrons

d) none of these)

4) Match the following correctly and select the answer using the codes given below :

Molecule Shape

I) Ammonia 1) Linear

II) Water 2) Planar

III) Boran trifluoride 3) V-shaped

IV) Carbon-di-oxide 4) Pyramid

a b c d

a) 3 2 1 4

b) 3 1 4 2

*c) 4 3 2 1

d) 1 2 3 4

5) The commonly used refrigerant in fridges is

a) ammonia

b) liquid nitrogen

c) liquid oxygen

*d) freons

6) Match the items of list I with list II and select the correct answer using codes given below the lists

List – I List – II

I) Tollen’s reagent 1) Cupric acetate in acetic acid

II) Bardoed’s reagent 2) Mixture of CuSO4 sodium citrate and Na2 CO3

III) Molisch reagent 3) Ammonical silver nitrate solution

IV) Benedict’ssolution 4) Alcoholic 2 naphthol and conc)H2 SO4

a b c d

*a) 3 1 4 2

b) 2 1 4 3

c) 2 3 1 4

d) 4 3 1 2

7) Match list I correctly with list II and select your answer using the codes given below the lists:

List – I List – II

I) Cinnabar 1) PbS

II) Zinc blende 2) HgS

III)Galena 3)Al2o3,2h2o

IV) Bauxite 4) ZnS

a b c d

a) 2 1 4 3

*b) 2 4 1 3

c) 1 3 4 2

d) 3 1 4 2

8) Sodium thiosulphate is widely used in photography. Its main role in photographic process is due to

*a) reduction

b) oxidation

c) complex formation

d) photo decomposition

9) If the percentage of oxygen in a metallic oxide in 33)33% then its equivalent mass is

a) 66

b) 16

*c) 32

d) 50

10) In nature borax occure as

*a) Tincal

b) Colemanite

c) Tridymite

d) Borasite