Question

The most important constituents in Gas mask is

• A. Charcoal
• B. Silica gel
• C. Caustic soda
• D. Hopcolite

Hint:

For mine fire escape respirators, the 1 killer is Carbon Monoxide (CO).
The chemical that specifically targets and neutralizes CO is Hopcolite.
Therefore, Hopcolite is the most vital ingredient.

Answer 1

The Correct Option is D

Step 1: Understanding the Question:
The question asks for the most important active ingredient in a gas mask, specifically in the context of a mine emergency where carbon monoxide is the primary threat.

Step 2: Detailed Explanation:
The type of "gas mask" used for escaping a mine fire is a Filter Self-Rescuer (FSR).
Its primary and most critical function is to protect the wearer from inhaling deadly Carbon Monoxide (CO) gas, which is produced during fires and explosions.
Let's analyze the roles of the substances listed:
-

Charcoal (Activated Carbon): This is an excellent adsorbent for a wide range of organic vapors and fumes, but it is ineffective at removing carbon monoxide.
-

Silica gel: This is a desiccant, used to absorb moisture from the incoming air.
This is important because the catalyst that removes CO works best in dry conditions.
-

Caustic soda: This is used to remove acidic gases like carbon dioxide (CO\(_2\)) or sulfur dioxide (SO\(_2\)).
-

Hopcolite: This is the crucial component.
It is a catalyst (typically a mixture of manganese dioxide and copper oxide) that promotes the oxidation of highly toxic carbon monoxide (CO) into much less harmful carbon dioxide (CO\(_2\)) at ambient temperatures.
\[ 2\text{CO} + \text{O}_2 \xrightarrow{\text{Hopcolite}} 2\text{CO}_2 \] Since CO is the main life-threatening gas in a mine fire atmosphere, Hopcolite is the most important constituent.

Step 3: Final Answer:
The most important constituent in a mine escape gas mask is Hopcolite.
This corresponds to option (D).