A 500-ML Sample of 2

Multiple Choice

A 50.0-mL sample of 2.0 × 10^-4 M CuNO₃ is added to 50.0 mL of 4.0 M NaCN. Cu⁺ reacts with CN^- to form the complex ion Cu(CN) ₃^2-: The concentration of Cu⁺ at equilibrium is

A) 5.0 × 10^-14 M.
B) 1.2 × 10^-14 M.
C) 2.0 × 10^-4 M.
D) 1.0 × 10^-4 M.
E) none of these