Question
Question: The solubility of \(AgBr{O_3}\) (formula weight \( = 236\)) is \(0.0072\,g\) in \(1000\,mL\). What i...
The solubility of AgBrO3 (formula weight =236) is 0.0072g in 1000mL. What is the value of Ksp?
A. 2.2×10−8
B. 3×10−10
C. 3×10−5
D. 9.3×10−10
Solution
The solubility product of an ionic compound is defined as the equilibrium constant for dissociation of a solid (ionic) substance into an aqueous solution. It is represented by the symbol Ksp. As the solubility of a solid increases with an increase in temperature, so the value of solubility product increases on increasing the temperature.
Complete answer: As per question, the given data is as follows:
Given mass of AgBrO3=0.0072g
Molecular mass of AgBrO3=236gmol−1
Therefore, number of moles of AgBrO3=molecular massgiven mass
Substituting values:
⇒n=2360.0072
⇒n=3.05×10−5moles
Given volume of solution=1000mL
⇒V=1L
We know that the concentration of a compound is the ratio of number of moles to the volume of solution. Therefore, concentration of AgBrO3 in aqueous solution will be as follows:
Concentration C=Vn
Substituting values:
⇒C=13.05×10−5
⇒C=3.05×10−5molL−1
Now, the dissociation of AgBrO3 in aqueous solution takes place as follows:
AgBrO3⇌Ag++BrO3−
ICE table for the concentration of molecules in the given reaction is as follows:
| [AgBrO3]| [Ag+]| [BrO3−]
---|---|---|---
Initial concentration| 3.05×10−5molL−1| 0| 0
Change| −3.05×10−5| +3.05×10−5| +3.05×10−5
Concentration at equilibrium| 0| 3.05×10−5molL−1| 3.05×10−5molL−1
Therefore, the solubility product of AgBrO3 can be expressed as follows:
Ksp=[Ag+][BrO3−]
Substituting the values of final concentration from ICE table:
⇒Ksp=3.05×10−5×3.05×10−5
⇒Ksp=9.3×10−10
Hence, the solubility product of AgBrO3 under given conditions =9.3×10−10.
So, option (D) is the correct answer.
Note:
It is important to note that in ICE table, I stands for initial concentration of reactants and products, C stands for change in concentration i.e., the concentration of compounds required for a reaction to achieve equilibrium and E stands for equilibrium concentration i.e., the concentration of reactants and products after achieving equilibrium.