Hydrogenation raises melting point of vegetable oils

Steps:

• Vegetable oils are unsaturated fats with many carbon-carbon double bonds, remaining liquid at room temperature.
• Margarine is produced by partial hydrogenation of vegetable oil, adding hydrogen to some double bonds.
• This process reduces unsaturation, making the fat more saturated and solid at room temperature.
• Saturated fats have higher melting points than unsaturated fats due to stronger intermolecular forces.

Why C is correct:

• Hydrogenation saturates double bonds, increasing van der Waals forces and thus raising the melting point, as defined by fat chemistry principles.

Why the others are wrong:

• A: Vegetable oil is liquid, but margarine is solid at room temperature.
• B: Margarine is artificially processed, while vegetable oil occurs naturally.
• D: Vegetable oil has more carbon-carbon double bonds than the hydrogenated margarine.

Final answer: C