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Combustion and Flame — Science STD 8 — Question

Gujarat BoardEnglish MediumSTD 8ScienceCombustion and Flame1 Mark
MCQ
Which of the following statement is not correct about carbon dioxide acting as a fire extinguisher for electrical fires?
  • A
    It is heavier than air.
  • ✓
    It is lighter than air.
  • C
    It is not combustible.
  • D
    It does not support combustion.
✓

Answer

Correct option: B.
It is lighter than air.
Carbon dioxide is lighter than air and forms a layer around the burning substance. It covers the fire like a blanket due to which fresh air cannot reach the burning substance.

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