Question
Chemistry Question on Equilibrium
Some chemists at ISRO wished to prepare a saturated solution of a silver compound and they wanted it to have the highest concentration of silver ion possible. Which of the following compounds, would they use? Ksp(AgCl)=1.8×10−10 Ksp(AgBr)=5.0×10−13 Ksp(Ag2CrO4)=2.4×10−12
A
AgCl
B
AgBr
C
Ag2CrO4
D
None of these
Answer
Ag2CrO4
Explanation
Solution
For binary salts (like AgCl,AgBr )
s=Ksp
∴ Solubility of AgCl=1.8×10−10
=1.35×10−7mol/L
Solubility of AgBr=5.0×10−13
=7.1×10−7mol/L
For, Ag2CrO4,Ksp=4s3
∴ Solubility of Ag2CrO4
=34Ksp=342.4×10−12
=3600×10−15
=8.44×10−5mol/L
As Ag2CrO4 has maximum solubility, it will give maximum Ag+ions in solution. Hence, it will be used.