Home PYQs UPPSC UPPSC MCQs Prelims 1996 (GS Paper I)

Question

Tetraethyl lead (TEL) is added to petrol:

  1. To prevent its freezing
  2. To increase its flash point
  3. To increase anti-knocking rating
  4. To increase its boiling point

Answer:

Option C: To increase anti-knocking rating

Detailed Solution:

The correct answer is “To increase anti-knocking rating”.

It prevents the engine from knocking by delaying the combustion process. However, due to its harmful environmental effects, its use has been phased out in most countries.