To increase the octane number, ______ is added to petrol.
A
1,2-ethyl alcohol
B
Butene
C
Tetraethyl lead
D
Power booster
Correct Option:
C
Explanation
Tetraethyl lead (TEL) was historically added to petrol as an anti-knock agent to increase its octane rating. It reduces premature combustion or “knocking.” Leaded petrol was later phased out because lead is highly toxic and causes serious environmental and neurological damage.
