Question

pH of 0.05 M $\left(C{H}_{3}COO{)}_{2}Ca\right(p{K}_a=4.74)$ is -

• A. 8.72
• B. 8.87
• C. 7
• D. 1.3

Answer 1

The correct option is B 8.87

$\left[C{H}_{3}CO{O}^{-}\right]=2\times 0.05=0.1$

$pH=\frac{1}{2}[p{K}_w+p{K}_a+logC]$


$=\frac{1}{2}[14+4.74+log0.1]$


$=\frac{1}{2}[14+4.74-1]=8.87$