Multiple choice

Natural gas is odorless. A smell like a "rotten egg" is added  before it is sold. What is this?

  1. alcohol

  2. sulfonamide

  3. mercaptan

  4. nitrous gas

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Mercaptan is a sulfur-containing compound added to natural gas because it has a distinct, unpleasant odor that allows leaks to be detected easily. Natural gas itself is odorless and colorless.