What mass of sodium cyanide (NaCN) must be added to 250 mL of 0.45 M Hydrocyanic acid (HCN) to produce a buffer solution that has a pH of 8.75?
(M.WNaCN: 49 g/mol, Канси: 6.2 x 10⁻¹⁰).
a. 322.96 g
b. 31.66 g
c. 1.93 g
d. 3.84 g
e. 15.83 g