GC questions

[emminent]

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Consider an acetate buffer, initially at the same pH as its pKa (4.76). When sodium hydroxide (NaOH) is mixed with this buffer, the:
7%
A:
pH remains constant.

12%
B: pH rises more than if an equal amount of NaOH is added to an acetate buffer initially at pH 6.76.

12%
C: pH rises more than if an equal amount of NaOH is added to unbuffered water at pH 4.76.

1%
D:sodium acetate formed precipitates because it is less soluble than acetic acid.

68%
E:[Correct]
ratio of acetic acid to sodium acetate in the buffer falls.

Can someone explain the reasoning behind the answers please for B/C. Also, E is correct b/c OH mixes with the buffer which lowers the ratio correct?

 

[TheEpicFruitCake]

look at what pKa = pH means.

hint: it means you're at a certain equilibrium

B and C are the exact opposite of the idea of a buffer. They resist changes in pH, not increase them