Question

Best fuel for S.I. engines is -
1. Aromatic
2. Naphthalene
3. Paraffins
4. Olefins

Answer 1

Correct Answer - Option 1 : Aromatic

Explanation:

• For SI engines the aromatics are the best fuel and the paraffin are least desirable.
• For CI engines, normal paraffin is the best fuel and aromatics are the least desirable.
• The reason for this is normal paraffin exhibit the poorest antiknock quality when used in SI engines. But the antiknock quality improves with the increasing number of carbon atoms and the compactness of the molecular structure. The aromatics offer the best resistance to knocking in SI Engines.