Manufacturers make vegetable oils solid or semisolid at room temperature by __________.

• A. removing hydrogen atoms and forming additional double bonds in the fatty acid hydrocarbon chains
• B. removing hydrogen atoms and forming additional single bonds in the fatty acid hydrocarbon chains
• C. adding hydrogen atoms to the single-bonded carbon atoms of the fatty acid hydrocarbon chains
• D. None of the listed responses is correct.
• E. adding hydrogen atoms to the fatty acid hydrocarbon chains, thereby converting carbon-carbon double bonds to single bonds

Answer: (E)

Verified step by step guidance

1. Understand the process of hydrogenation: Hydrogenation is a chemical reaction that involves the addition of hydrogen (H₂) to unsaturated bonds, typically carbon-carbon double bonds, in organic compounds.
2. Identify the structure of unsaturated fatty acids: Unsaturated fatty acids contain one or more double bonds between carbon atoms in their hydrocarbon chains. These double bonds cause the fatty acids to be liquid at room temperature.
3. Recognize the goal of hydrogenation in vegetable oils: The purpose of hydrogenation is to convert unsaturated fatty acids into saturated ones by adding hydrogen atoms, which changes the double bonds to single bonds, making the oils solid or semisolid at room temperature.
4. Examine the options provided: The correct process involves adding hydrogen atoms to the fatty acid hydrocarbon chains, thereby converting carbon-carbon double bonds to single bonds. This is known as hydrogenation.
5. Conclude with the correct choice: The correct answer is 'adding hydrogen atoms to the single-bonded carbon atoms of the fatty acid hydrocarbon chains,' which aligns with the process of hydrogenation.