The pH of a buffer prepared by mixing 50 ml of `0.2 M CH_(3)COOH` and 25 ml of `CH_(3)COONa` is 4.8. If the `pK_(a)` is 4.8, what is the strength of `CH_(3)COONa`?

Explanation

For acidic buffer solution
`pH+pK_(a)+log(["Salt"])/(["Acid"])=pK_(a)+log(M_(1)V_(1))/(M_(2)V_(2))`
`M_(1)=` moles of salt?
`M_(2)=` moles of base 0.2
`V_(1)=` volume of salt 25
`V_(2)=` Volume of acid 50
`pH=4.8, pK_(a)=4.8`
When the [Salt]=[Acid] pH`=` pH
`:.M_(1)xx25=0.2xx50`
`M_(1)=(0.2xx50)/25=0.4M`