A buffer solution has equal volumes of 0.2 M `NH_(4)OH and 0.02 M NH_(4) CI` The `pk_(b)` of the base is 5. The pH is

Options

A. A) 10
B. B) 9
C. C) 4
D. D) 7

Answer

a

Explanation

`pOh=pK-(b)+log[sal t]/([base])`
`=5+log(0.02)/(0.2)=5+log(1)/(10)=5+(-1)=4`
`pH=14-pOH=14-4=10`