Question

Which of the following conditions is not necessary for burning?

• A. Presence of a combustible substance
• B. Presence of supporters of combustion
• C. Heating the combustible substance to its ignition temperature
• D. Presence of water

Answer 1

The correct option is D

Presence of water

The explanation for the correct option

(D) Presence of water.

• Water is a substance used to stop burning.
• Water is not a combustible substance.
• Therefore the presence of water is not necessary for burning.
• Thus option D is correct.

The explanation for the incorrect options

(A) Presence of a combustible substance

• Combustion means the process of burning. Or we can say it is the reaction between a hydrocarbon and oxygen.
• Therefore the presence of combustible substances will increase the chances of burning and it is necessary for burning.
• Thus option A is incorrect.

(B) Presence of supporters of combustion

• The supporter is a substance that supports the process of combustion.
• Therefore the presence of supporters will also be necessary for burning.
• Hence option B is incorrect.

(C) Heating the combustible substance to its ignition temperature

• Ignition temperature is the minimum temperature to ignite (or burn) a substance.
• Therefore heating the substance to its ignition temperature will only burn the substance. Thus it is also necessary for burning.
• Hence option C is incorrect.

Therfore the correct option is (D) Presence of water.