You Have Solutions of 0

Multiple Choice

You have solutions of 0.200 M HNO₂ and 0.200 M KNO₂ (K_a for HNO₂ = 4.00  10^-4) . A buffer of pH 3.000 is needed. What volumes of HNO₂ and KNO₂ are required to make 1 L of buffered solution?

A) 286 mL HNO₂; 714 mL KNO₂
B) 714 mL HNO₂; 286 mL KNO₂
C) 413 mL HNO₂; 587 mL KNO₂
D) 500 mL of each
E) 587 mL HNO₂; 413 mL KNO₂