The secret in the fire extinguisher

Fire extinguishers can be seen everywhere in public schools
As a standing fire-fighting tool, you have thought about how the absence of a fire extinguisher can work to make the fire extinguished quickly?

The winner of China’s “International Science and Technology Cooperation Award”, the distinguished professor of Beijing University of Chemical Technology, Dr. David G. Evans, use the following small experiment to demonstrate how a fire extinguisher can extinguish a fire
Come and have a look with me
The working principle of carbon dioxide fire extinguisher

Fire extinguisher experiment

 prepare baking soda first, add water to dissolve

Then insert the test tube containing white vinegar into the bottle

Put the bottle well
Baking soda and white vinegar are separated, and there will be no reaction inside

But if there is a fire, then shake the bottle
Mix white vinegar and baking soda

Let’s see their fire extinguishing effect

The fire went out soon
This is due to the chemical reaction between baking soda and white vinegar to produce new substances
This new substance is the gaseous carbon dioxide
But why is there so much foam in the bottle?

Because it contains detergent
This simple fire extinguisher uses white vinegar and baking soda to produce carbon dioxide.
After the carbon dioxide is ejected, the oxygen is driven away, the oxygen is getting less and less, and the flame is getting smaller and smaller.

This experiment includes the production principles of acid-base fire extinguishers and foam fire extinguishers
But most of what you usually see are dry powder fire extinguishers and carbon dioxide fire extinguishers
So let me introduce the working principle of carbon dioxide fire extinguisher

Fire knowledge for Carbon dioxide fire extinguisher

1. Carbon dioxide fire extinguisher is the main type of fire extinguisher.
2. The principle of carbon dioxide fire extinguisher: liquid carbon dioxide is placed in the carbon dioxide fire extinguisher, which becomes gaseous to absorb heat when sprayed out, thereby reducing the temperature of the fire site. The emission of carbon dioxide reduces the oxygen concentration, and even drives off the oxygen, isolating combustibles and oxygen, and the oxygen-deficient combustion will naturally go out.