What is the best way to determine the number of moles of acetic acid in vinegar during a titration with a strong base?

• A. It is not necessary to determine the number of moles of acetic acid.
• B. It will be equal to the initial concentration of acetic acid in the solution.
• C. It will be equal to the moles of NaOH used at the equivalence point.
• D. It will be equal to the moles of potassium hydrogen phthalate used to standardize the NaOH.

Answer: (C)

Verified step by step guidance

1. Understand that titration is a technique used to determine the concentration of a solute in a solution by reacting it with a standard solution of known concentration.
2. Recognize that in this problem, acetic acid (CH₃COOH) in vinegar is being titrated with a strong base, such as sodium hydroxide (NaOH).
3. Identify the equivalence point in the titration, which is the point at which the number of moles of the titrant (NaOH) equals the number of moles of the substance being titrated (acetic acid).
4. Use the balanced chemical equation for the reaction: CH₃COOH + NaOH → CH₃COONa + H₂O. This shows a 1:1 molar ratio between acetic acid and NaOH.
5. Determine the number of moles of acetic acid by calculating the moles of NaOH used at the equivalence point, as they are equal due to the 1:1 stoichiometry of the reaction.