UPSC Prelims 2008 Q115: Science & Technology – Health & Diseases

UPSC Prelims 2008, General Studies Paper I · Science & Technology

Mixture of which one of the following pairs of gases is the cause of occurrence of most of the explosions in mines?

Answer: (c) Methane and air

Explanation

Which gas mixture causes most mine explosions

Underground mining operations face a specific, well-known explosion hazard from gas accumulation.

Option	Verdict	Reason
(a) Hydrogen and oxygen	Incorrect	Not the typical cause of mine explosions
(b) Oxygen and acetylene	Incorrect	Also not the typical mine explosion cause
(c) Methane and air	Correct	Methane (firedamp) accumulating and mixing with air in mines is the primary cause of most mine explosions
(d) Carbon dioxide and methane	Incorrect	Carbon dioxide does not support combustion, so this mixture is not explosive

Mine explosion facts:

Point	Detail
Hazard gas	Methane (firedamp)
Explosive mixture	Methane + air

Answer: (c) Methane and air.

(a) Incorrect. Hydrogen and oxygen is not the typical mine explosion cause.
(b) Incorrect. Oxygen and acetylene is also not the typical cause.
(c) CORRECT. Methane and air mixtures (firedamp) cause most mine explosions.
(d) Incorrect. Carbon dioxide doesn't support combustion, making this mixture non-explosive.

Methane (firedamp) mixing with air is the primary cause of most mine explosions — not carbon dioxide mixtures, which don't support combustion.

Methane and air mixture is the cause of most mine explosions.

Confusing methane's explosive hazard with unrelated gas combinations.
Not knowing the term 'firedamp' for methane accumulation in mines.
Assuming carbon dioxide, despite being a gas, could support an explosive reaction.

Mine explosions = methane (firedamp) + air. A classic mining-safety hazard fact.