Solveeit Logo

Question

Question: When equal volumes of the following solutions are mixed, precipitation of AgCl ($K_{sp}$ = 1.8×10$^{...

When equal volumes of the following solutions are mixed, precipitation of AgCl (KspK_{sp} = 1.8×1010^{-10}) will occur only with

A

104^{-4}M (Ag+^+) and 104^{-4} M (Cl^-)

B

105^{-5} M (Ag+^+) and 105^{-5} M (Cl^-)

C

106^{-6} M (Ag+^+) and 106^{-6} M (Cl^-)

D

1010^{-10} M (Ag+^+) and 1010^{-10} M (Cl^-)

Answer

(a)

Explanation

Solution

When equal volumes of two solutions are mixed, the concentration of each solute is halved. Precipitation of AgCl occurs when the ionic product (QspQ_{sp}) exceeds the solubility product (KspK_{sp}). The ionic product is calculated as the product of the concentrations of Ag+^+ and Cl^- ions after mixing. For option (a), initial concentrations are 10410^{-4} M for both ions. After mixing equal volumes, concentrations become 0.5×1040.5 \times 10^{-4} M for each. The ionic product is (0.5×104)×(0.5×104)=0.25×108=2.5×109(0.5 \times 10^{-4}) \times (0.5 \times 10^{-4}) = 0.25 \times 10^{-8} = 2.5 \times 10^{-9}. The given KspK_{sp} is 1.8×10101.8 \times 10^{-10}. Since 2.5×109>1.8×10102.5 \times 10^{-9} > 1.8 \times 10^{-10}, precipitation occurs in this case. For other options, the calculated ionic product is less than the KspK_{sp}, so precipitation does not occur.