Question

$C{O}_2$ is used for extinguishing fire because

• A. it has a relatively high critical temperature
• B. in solid state, it is called dry ice
• C. it is neither combustible nor a supporter of combustion
• D. it is a colourless gas

Answer 1

The correct option is C it is neither combustible nor a supporter of combustion

Oxygen, fuel and heat are important for the combustion. If any one of these lacks, there won't be any combustion.
$C{O}_2$ is heavy and incombustible. It is also a non supporter of combustion. When it sprayed on burning object, it stops the supply of oxygen and extinguishes fire. Thus, it used in fire extinguisher.