Soda -Acid Fire Extinguisher Class 10

Today we will learn how to prepare soda acid fire extinguisher in the laboratory of our school.

You have noticed that a red coloured cylinder is fixed on the walls, this is a commercial fire extinguisher.

We will prepare the same soda acid fire extinguisher.

Material required for soda acid fire extinguisher

A soda acid fire extinguisher contains the following

i.        Sodium hydrogen carbonate

ii.     Dilute sulphuric acid

iii.   A wash bottle with a nozzle

Method  (Preparation of soda acid extinguisher)

We will take 20 mL sodium hydrogen carbonate solution in a wash bottle and suspend an ignition tube containing dilute sulphuric acid in the wash bottle.

Now we take a cork fix a nozzle in it and close the wash bottle with the cork.

 Now our soda acid fire extinguisher is ready.

Working of soda acid extinguisher

Now we will see how soda acid fire extinguisher works.

We take a burning candle.

We tilt the wash bottle so that the acid from the ignition tube mixes with the sodium hydrogen carbonate.

Observation 

We will notice effervescence ( a gas) coming out of the nozzle.

Now we direct this gas on a burning candle, and we notice that the candle blows out.

What happens

When sulphuric acid mixes with sodium hydrogen carbonate, a fast reaction takes place in which `CO2` along with steam is produced.

soda acid fire extinguisher reaction

`2NaHCO_3 +H_2SO_4 →Na_2SO_4 + 2H_2O + CO_2`

Conclusion

We can see that the burning candle is extinguished. This is because carbon dioxide gas is heavier than the air.

`CO_2` surrounds the fire and cuts off the supply of oxygen.

 

MCQs 

   1.  Which of the following materials in not required for preparing soda acid fire extinguisher?

a.   NaHCO3

b.  H2SO4

c.   HCl

d.  Wash bottle

Correct answer – (c) HCl

   2.  Which gas is produced in soda acid fire extinguisher?

a.   CO

b.  CO2

c.   SO2

d.  None of the above

Correct answer – (b) CO2

   3.  What is the nature of sodium hydrogen carbonate?

a.   Acidic

b.  Alkaline

c.   Neutral

d.  None of the above

Correct answer – (b)

    4.  Which compound or substance is used in a soda acid fire extinguisher?

a.   Washing soda

b.  Caustic soda

c.   Baking soda

d.  Common salt

Correct answer – (c)

   5.  Which acid is used in a soda acid fire extinguisher?

a.   Hydrochloric acid

b.  Nitric acid

c.   Sulphuric acid

d.  Acetic acid

Correct answer – ( c) 

   1.  Which  gas is produced in a soda acid fire extinguisher?

Ans – Carbon dioxide is produced in soda acid fire extinguishers.

   2.  Which chemical is used in soda acid fire extinguishers?

Ans – Sodium hydrogen carbonate and dilute sulphuric acid.

   3.  Why baking soda is used in soda acid fire extinguishers?

Ans – Baking soda reacts with sulphuric acid to produce `CO_2` which extinguishes the fire.

   4.  Why is carbon dioxide an effective fire extinguishing agent in a soda acid fire extinguisher?

Ans – `CO_2` is a heavier gas than the air. It forms a blanket around the fire and cuts off the supply of oxygen.