alleryStart learning →Sodium acetate is dissolved in water. What does the acetate ion do?
AIt donates protons, lowering the pH value
BIt takes protons from water, raising the pH
CIt stays a spectator, leaving the pH alone
DIt precipitates, removing acid from solution
Answer & Solution
Correct answer: B. It takes protons from water, raising the pH
1. This salt comes from the weak acid acetic acid and the strong base sodium hydroxide.
2. Sodium ion has no effect on the acidity of the solution.
3. Acetate is the conjugate base of a weak acid, so it is itself a weak base.
4. It takes a proton from water, forming acetic acid and hydroxide ion.
5. The extra hydroxide raises the pH, making the solution weakly basic.
_Source: OpenStax Chemistry (CC BY 4.0), Ch 14 "Acid-Base Equilibria", section 14.4 Hydrolysis of Salt Solutions_
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