Question

Select the compound that is most likely to increase the solubility of AgCl when added to water.    KClO4, MgBr2, NH3, NaCl

Answer 1

Solution.

The solubility of AgCl is related to its solubility product:

$[Ag^{+}][Cl^{-}]=K_{sp};$

$K_{sp}=1.8\times 10^{-10};$

so, the solubility in the pure water is quite low.

However, the addition of ammonia will cause the formation of complex ions:

$Ag^{+}+ 2NH_3 \Rightarrow Ag(NH_3)_2^{+}; K_{eq} = 1.7\times 10^{7};$

As a result, the solubility of AgCl can be significantly increased by the addition of NH₃.