[blackzx6r]

 A 150 mL solution has 0.95 M HCN and a solution of 0.1 M NaCN. What is the volume of the
0.1 M NaCN solution that you should use to obtain a pH of 8.5 (it may not be possible to get this -10
pH). Be careful with the volume changes. Ka = 4.8 x 10

that is the question.. i spend an hour reading the chapter in the book again.. i am soo lost, dont even know how to start this...

[Borek]

This is a solution containing acid and conjugate base, these solutions have specific name and are usually described using specific equation.