A 50 ml aliquot of 0.05 M NaCN (Ka for HCN = 6.2* 10-10) is titrated with 0.1 M HCI. The reaction is CN + H, O* Calculate the PH after the addition of (a) zero ml (b) 10 ml (c) 25 ml (d) 26 ml of acid and draw the titration HEN +H,0 curve.