In gasoline (petrol) formulation, why are antioxidants added to the fuel blend?

Introduction:Gasoline stability is affected by oxidation of unsaturated components, which can form gums and deposits. Antioxidant additives interrupt radical chain reactions responsible for gum formation.

Given Data / Assumptions:

• Fuel: gasoline (petrol).
• Additive: antioxidants (e.g., phenolic or amine types).

Concept / Approach:Antioxidants act as radical scavengers, slowing oxidation that otherwise forms high-molecular-weight gums. This preserves storage stability and protects fuel systems.

Step-by-Step Solution:1) Identify the degradation pathway: oxidation leads to gum formation.2) Match additive function: antioxidants inhibit oxidation chain reactions.3) Conclude purpose: reduce gum formation in service and storage.

Verification / Alternative check:Fuel specifications and additive supplier literature consistently associate antioxidants with improved oxidation stability and reduced gum.

Why Other Options Are Wrong:Colour identification: Dye additives, not antioxidants, impart colour.Prevent icing: Anti-icing agents or alcohols address carburettor icing.Prevent lead build-up: Lead scavengers historically addressed deposits when leaded gasoline was used.Increase RVP: Volatility modifiers, not antioxidants, affect RVP.

Common Pitfalls:Confusing antioxidants with detergents, metal deactivators, dyes, or volatility improvers; each addresses different performance properties.

Final Answer:To minimise gum formation by inhibiting oxidation