Question

A substance can produce flame only when it

Options:
A:Vapourises
B:Condenses
C:Solidifies
D:All

Which is the right answer?

Answer 1

A substance can produce flame only when it vaporizes.

Why are gases more flammable?

• A substance will become flammable when the thermal energy increases.
• Gases, when vaporizing. can be flammable as molecules in a gas have the highest thermal energy.
• Other options, like option B condenses, is not correct because during condensation, the molecules change from a gas which has high thermal energy to a liquid which has lower thermal energy.

Hence, the correct option is A. Vaporizes.

Answer 2

Explanation:

Vapourises..................