A Solution Is Prepared by Mixing 50

Multiple Choice

A solution is prepared by mixing 50.0 mL of 0.50 M Cu(NO₃) ₂ with 50.0 mL of 0.50 M Co(NO₃) ₂. Sodium hydroxide is added to the mixture. Which hydroxide precipitates first and what concentration of hydroxide ions present in solution will accomplish the separation? K_sp = 2.2 × 10⁻²⁰ for Cu(OH) ₂, K_sp = 1.3 × 10⁻¹⁵ for Co(OH) ₂

A) Co(OH) ₂; [OH ⁻] = 6.9 × 10 ⁻⁶ M
B) Co(OH) ₂; [OH ⁻] = 2.6 × 10 ⁻⁷ M
C) Cu(OH) ₂; [OH ⁻] = 1.8 × 10 ⁻⁷ M
D) Cu(OH) ₂; [OH ⁻] = 1.1 × 10 ⁻⁹ M
E) Cu(OH) ₂; [OH ⁻] = 1.0 × 10 ⁻¹⁷ M