In a buffer solution consisting of NaCN and HCN, [NaCN] = 0.18(M) and [HCN) = 0.16(M). If 2 millimoles of HCl is added to 100mL of this buffer solution (assuming volume of the solution remains the same because of the addition of HCl), then pH of the buffer will-

Options

A. increase by 0.021 unit
B. decrease by 0.102 unit
C. increase by 0.11 unit
D. decrease by 0.012 unit

Answer

B