Question

Which of the following is mainly produced by the activity of anaerobic bacteria on sewage?

• A. Marsh gas
• B. Propane
• C. Mustard gas
• D. Laughing gas

Answer 1

The correct option is A

Marsh gas

The correct option is A:

Explanation for Correct option:

1. Methane is also called marsh gas because it is produced by the anaerobic bacterial decomposition of vegetable matter under water or in a marshy area.
2. The decomposition of sludge by anaerobic bacteria in sewage-treatment processes also produces a gas rich in methane.

Explanation for Incorrect option:

Option B:

Its main uses include home and water heating, cooking and refrigerating food, clothes drying, and powering farm and industrial equipment.

Option C:

Mustard gas has a long history of being used as a weapon in warfare and is one of the most well-studied of such agents.

Option D:

Nitrous oxide is clinically used as a safe anesthetic in dentistry, ambulance, and childbirth and is appreciated for its anti-anxiety effect.

Final answer:

Marsh gas is produced by the activity of anaerobic bacteria on sewage.