Help needed on a homework problem -
solution of HCN and CN- , Ka 6.2x10^-10 . Is this a buffered solution? Shouldn't the pH be greater than 7, and [OH] >[H]?
Does adding a strong acid have more effect than adding a strong base?
Thanks.
1 answer
A solution of HCN and CN^- is the solution of a weak acid and it's salt; therefore, it is a buffered solution. Look at the Henderson-Hasselbalch equation and see what the pH is for say 0.1M HCN and 0.1 M CN^-. Adding a strong acid versus adding a strong base--about the same effect although one gets more acidic and the other becomes more basic.