nature of matter and composition - Category wise Question and Answer Practice Test with Solutions

Question : 26 [NDA]

Which of the following is the best example of the law of conservation of mass?

a) A sample of air increases in volume when heated at constant pressure but mass remains unchanged

b) When 12 gm of carbon is heated in vacuum, there is no change in mass

c) Weight of platinum wire is the same before and after heating

d) 12 gm of carbon combines with 32 gm of oxygen to give 44 gm of carbondioxide.

Question : 27

The chemical name of 'Marsh gas' is

a) Propane

b) Ethene

c) Methane

d) Hexane

Question : 28

Select the one that is a physical change.

a) Rusting of iron

b) Growth of plant

c) Digestion of food

d) None of these

Question : 29

The boiling point of alcohol is 78°C. What is this temperature in Kelvin scale

a) 375 K

b) 373 K

c) 351 K

d) 78 K

Question : 30 [NDA]

Match the following columns ?

a) A - 3, B - 4, C - 2, D - 1

b) A - 2, B - 1, C - 3, D - 4

c) A - 2, B - 4, C - 3, D - 1

d) A - 3, B - 1, C - 2, D – 4