Exhibit 2B
Contains information on the pK's of some common buffers.
$\begin{array}{llrc}
\text { Buffer } & \mathbf{p K} 1 & \mathbf{p K 2} & \mathbf{p K} 3 \
\hline \text { Acetate } & 4.75 & & \
\text { Ammonia } & 9.25 & & \
\text { Carbonic acid } & 6.37 & 10.20 & \
\text { Citric acid } & 3.09 & 4.75 & 5.41 \
\text { Formic Acid } & 3.75 & & \
\text { Phosphoric acid } & 2.14 & 7.20 & 12.4 \
\text { Pyruvic acid } & 2.50 & & \
\text { Tris } & 8.3 & &
\end{array}$

-Refer to Exhibit 2B. Which of the following would make the best buffer at pH =10.0?

Question

Exhibit 2B
Contains information on the pK's of some common buffers.
$\begin{array}{llrc}
\text { Buffer } & \mathbf{p K} 1 & \mathbf{p K 2} & \mathbf{p K} 3 \
\hline \text { Acetate } & 4.75 & & \
\text { Ammonia } & 9.25 & & \
\text { Carbonic acid } & 6.37 & 10.20 & \
\text { Citric acid } & 3.09 & 4.75 & 5.41 \
\text { Formic Acid } & 3.75 & & \
\text { Phosphoric acid } & 2.14 & 7.20 & 12.4 \
\text { Pyruvic acid } & 2.50 & & \
\text { Tris } & 8.3 & &
\end{array}$

-Refer to Exhibit 2B. Which of the following would make the best buffer at pH =10.0?

Quizplus · Accepted Answer

The best buffer is one where the pH is close to the pK value. For pH = 10.0, the pK2 of carbonic acid (10.20) is closest, making NaHCO3 and Na2CO3 the best choice.

Exhibit 2B Contains Information on the PK's of Some Common

Exhibit 2B
Contains Information on the PK's of Some Common