Chemistry MCQs

Question 1

When lime juice is dropped on baking soda, brisk effervescence takes place because the gas evolved is

Accepted Answer

Carbon dioxide

Answer

Hydrogen

Answer

Oxygen

Answer

All of them

Question 2

Which of the following is used as filler in tyre of rubber ?

Accepted Answer

Carbon black

Answer

Coal

Answer

Coke

Answer

Graphite

Question 3

The open "Sigrees" or coal stoves often require fanning to sustain burning because of

Accepted Answer

Tendency of carbon dioxide to form a layer along with dust smoke

Answer

Lack of oxygen in the surroundings of sigrees

Answer

Accumulation of smoke and dust over the sigrees

Answer

Interrupted release of moisture from the material

Question 4

24 carat of diamond is equal to

Accepted Answer

480 mg

Answer

200 g

Answer

95% mg

Answer

91% gold

Question 5

1 carat of diamond is equal to

Accepted Answer

200 mg

Answer

200 g

Answer

100 mg

Answer

100 g

Question 6

The most pure form of Carbon among the options is

Accepted Answer

Anthracite

Answer

Lampblack

Answer

Graphite

Answer

Wood Charcoal

Question 7

Carbon footprint can be reduced by

Accepted Answer

All of these

Answer

Recycling waste materials

Answer

Using energy efficient appliances

Answer

Commuting by public transport

Question 8

Which of the following gases is most toxic ?

Accepted Answer

Carbon monoxide

Answer

Carbon dioxide

Answer

Sulphur dioxide

Answer

Chlorine

Question 9

Why is water not suitable for putting out a petrol fire ?

Accepted Answer

Water, being heavy, slips below petrol which thus remains in contact with air and burns

Answer

The oxygen content of water is isolated by petrol and thus it helps in burning

Answer

Petrol is too inflammable to be extinguished by water

Answer

The heat required for combustion of petrol is very low