50 ml of 0.1 M solution of sodium acetate and 50 ml of 0.01 M acetic acid are mixed. The $p{K}_a$of acetic acid is 4.76. The pH of the buffer solution is _____.

pH = $p{K}_a+log\frac{salt}{acid}$

 [salt] = $\frac{50\times 0.1}{100}$ = 0.05

[Acid] = $\frac{50\times 0.01}{100}$ = 0.005

pH = $p{K}_a+log\frac{salt}{acid}$

= 4.76 + log $\frac{0.05}{0.005}$

= 4.76 + log 10 = 4.76 + 1 = 5.76.

Hence, the answer is 5.76.