Question

The fire produced by oil cannot be controlled by

• A. a) ${\mathrm{CO}}_2$
• B. b) Foam
• C. c) Water
• D. d) Both a and b

Answer 1

The correct option is C

c) Water

A correct answer is option (C) water.

The explanation for the correct answer-

1. When we add water to the fire caused by oil, then the fire expands more.
2. It happens because the specific gravity of the water is high compared to oil.
3. That's why when we add water to a fire caused by oil, then oil floats on the water, and despite that, the fire expands.
4. Therefore, water is not supposed to be used to stop fires caused by oil.

The explanation for incorrect answer -

Option(A) ${\mathrm{CO}}_2$

1. Carbon dioxide${\mathrm{CO}}_2$ displaces the oxygen gas which is present in the surrounding environment of the fire.
2. Carbon dioxide is very cold in nature therefore, it cools the oil very quickly and extinguishes the fire in less time.

Option(B) Foam

1. Foam forms a blanket-like structure on oil surface to reduce the fire flames.
2. The foam separates the surface of the oil from oxygen and cools the oil.
3. Then the fire extinguishes easily.

Hence, Carbon dioxide and Foam can be used to put off the fire while water is not used for oil fire. So, option c is the correct option.