Question

In the following set up for burning ammonia in oxygen, ammonia tube is fitted higher and oxygen tube is kept lower because?

P Oxygen is lighter than ammonia.

Q Ammonia is lighter than oxygen.

R Ammonia and oxygen mixture is explosive and by keeping them in this position, limited oxygen will react with ammonia.

Which of the following is true?

Options

• Only P

• Only Q

• Only R

• Both P and Q

Answer 1

Only Q

Explanation:

Ammonia (NH₃) has a molecular mass of 17, while oxygen (O₂) has a molecular mass of 32. Therefore, ammonia is lighter than oxygen.

So:

P: False

Q: True

R: False

Hence, the correct option is (b) Only Q.