Question

Which of the following substance can be used to make a fire extinguisher?

• A. Baking soda
• B. Washing soda
• C. Bleaching powder
• D. Common salt

Answer 1

The correct option is A

Baking soda

A fire-extinguisher generally consists of baking soda and vinegar. The role of a fire extinguisher is to extinguish the fire by releasing carbon-dioxide which does not support combustion. So, the reaction which is the principle behind the working of fire extinguisher is the reaction between an acid and a metal bicarbonate. Acids react with a metal bicarbonate to form a metal salt, carbon-dioxide gas and water.

$Acid\left(aq\right)+MetalBicarbonate\left(s\right)\to MetalSalt\left(s\right)+H_{2}O\left(l\right)+C{O}_2\left(g\right)$

The reaction between acetic acid and baking soda is:

$C{H}_{3}COOH\left(aq\right)+NaHC{O}_3\left(s\right)\to C{H}_{3}COONa\left(s\right)+H_{2}O\left(l\right)+C{O}_2\left(g\right)$