A buffer solution is prepared by mixing 10 mL of 1.0 M acetic acid and 20 mL of 0.5 M sodium acetate acid and then diluted to 100 mL with distilled water. If the pKa of CH3COOH is 4.76, what is the pH of the buffer solution prepared ?

Question

A buffer solution is prepared by mixing 10 mL of 1.0 M acetic acid and 20 mL of 0.5 M sodium acetate acid and then diluted to 100 mL with distilled water. If the pKa of CH3COOH is 4.76, what is the pH of the buffer solution prepared ? (A) 5.21 (B) 4.76 (C) 4.34 (D) 5.22

Tardigrade Admin · Accepted Answer

The expression for the pH of the acidic buffer solution is as given below. pH = pK a + log ([ text Salt ]/[ text Acid ]) pK a =4.76 [Salt] =(20 × 0.5/100)=0.1 M [Acid] =(10 × 1/100)=0.1 M Substitute values in the above equation. pH =4.76+ log (0.1/0.1)=4.76

Q. A buffer solution is prepared by mixing 10 mL of 1.0 M acetic acid and 20 mL of 0.5 M sodium acetate acid and then diluted to 100 mL with distilled water. If the pKa​ of CH3​COOH is 4.76, what is the pH of the buffer solution prepared ?

5.21

4.76

4.34

5.22

The expression for the pH of the acidic buffer solution is as given below. pH=pKa​+log[ Acid ][ Salt ]​ pKa​=4.76 [Salt] =10020×0.5​=0.1M [Acid] =10010×1​=0.1M Substitute values in the above equation. pH=4.76+log0.10.1​=4.76

Q. A buffer solution is prepared by mixing 10 mL of 1.0 M acetic acid and 20 mL of 0.5 M sodium acetate acid and then diluted to 100 mL with distilled water. If the $p K_{a}$ of $C H_{3} COO H$ is 4.76, what is the pH of the buffer solution prepared ?