K_a for HCN is 5xx10^(-10) at a certain temperature. For maintaining a constant pH of 9, what is the volume of 5M KCN solution required to be added to 10ml. of 2M HCN?
1 Answer
Oct 8, 2017
2mL.
Explanation:
KCN and HCN make a tampon solution with pH that you can calculate with the formule
If pH must be 0 you have
therefore
Since
mol of acid are :
so you need 0.01 mol of salt whose volume is :