Chemistry
Grade-8
Easy
Question
Assertion-Reason Type Questions
Assertion (A): CO2 is used in fire extinguishers to put off fires.
Reason (R): It is a non-combustible gas and supports combustion.
- Both A and R are true, and R is the correct explanation of A.
- Both A and R are true, but R is not the correct explanation of A
- A is true, and R is false.
- A is false, and R is true.
Hint:
Fire extinguishers doesn't contain oxygen as it supports combustion/fire.
The correct answer is: A is true, and R is false.
The correct option is c)A is true, and R is false.
Carbon dioxide extinguishes work by displacing oxygen which is an important element for combustion. The carbon dioxide coming out of the fire extinguisher is also very cold, so it cools the fuel as well.
The reason is wrong as carbon dioxide doesn't support combustion which is the reason why it is used in fire extinguishers.
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