What is a Soda Acid Fire Extinguisher?

Soda-acid fire extinguishers comprises of sodium bicarbonate and sulphuric acid. It is the most efficient house-hold fire extinguisher. It consists of a strong iron vessel with a side discharge nozzle. The iron vessel is filled with a sodium bicarbonate solution.

Working

The working principle of any fire extinguisher is based on the following three conditions:

• cooling of the combustible material below its ignition temperature
• cutting off the air supply
• cooling the combustible material simultaneously while cutting off the air supply.

Reaction

• There is a solution of sodium bicarbonate in water in the fire extinguisher and sulphuric acid in a different bottle within it.
• The sulphuric acid is combined with sodium bicarbonate solution and creates an amount of carbon dioxide gas when the fire extinguisher is operated by turning the knob on it.
• Carbon dioxide gas is not combustible, nor does it endorse combustion.
• It is heavier than air and cuts off the air’s supply of oxygen, thus extinguishing the flames.

The following reaction takes place
2NaHCO ₃+H ₂SO ₄→Na ₂SO ₄+2H ₂​ O+2CO ₂
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