Chemistry MCQs

Question 1

The process which does not evolve CO 2 in air is

Accepted Answer

Photosynthesis

Answer

Burning

Answer

Breathing

Answer

Organic delay

Question 2

An oxidising agent is a

Accepted Answer

An electron acceptor

Answer

An electron donor

Answer

In a chemical reaction its oxidation number increases

Answer

It releases H 2 in a chemical reaction

Question 3

Copper substances when exposed to air gains a green coating due to the formation of:

Accepted Answer

CuCO 3 Cu(OH) 2

Answer

CuO

Answer

CuSO 4

Answer

Cu(NO 3 ) 2

Question 4

It is dangerous to leave the car engine running in a closed garage, because it may cause serious pollution due to poisoning by emission of

Accepted Answer

CO

Answer

CO 2

Answer

Unburnt petrol

Answer

SO 2

Question 5

Main pollutants released from iron and steel industry are

Accepted Answer

CO, CO 2 and SO 2

Answer

NO, SO 3 and H 2 S

Answer

CO 2 , H 2 S and NO 2

Answer

CO 2 , NO 2 and SO 3

Question 6

The presence of Cobalt in Vitamin B 12 was established for the first time by

Accepted Answer

Spectroscopy

Answer

Hydrolysis test

Answer

Borax-Bead test

Answer

Sodium Nitroprusside test

Question 7

What is the mass percentage of oxygen in carbon dioxide (CO 2 )?

Accepted Answer

72.7 %

Answer

30.5%

Answer

50.9 %

Answer

65.8 %

Question 8

The formula C 6 H 5 -CO-CH 3 represents

Accepted Answer

Acetophenone

Answer

Acetone

Answer

Acetic acid

Answer

Phenyl acetate

Question 9

Which among the following is used as a catalyst in the production of high octane fuels?

Accepted Answer

H 2 SO 4

Answer

HNO 3

Answer

HCl

Answer

HF