NTA Abhyas JEE Main2020ChemistryIonic EquilibriumPractice
A g B r ( s ) + 2 S 2 O 3 2 - ( a q ) ⇌ A g ( S 2 O 3 ) 2 3 - ( a q ) + B r - ( a q ) Given K s p ( A g B r ) = 5 × 1 0 - 13 ; K f A g ( S 2 O 3 ) 2 3 - = 5 × 1 0 13 What is the molar solubility of AgBr in 0.1 M N a 2 S 2 O 3 ?
Options
- A0.5 M
- B0.45 M
- C0.045 M
- DNone of these
Correct answer
C. 0.045 M
Step-by-step solution
A g B r ( s ) ⇌ A g + ( a q ) + B r - ( a q ) K s p A g + ( a q ) + 2 S 2 O 3 2 - ( a q ) ⇌ A g ( S 2 O 3 ) 2 3 - ( a q ) K f A g B r s + 2 S 2 O 3 2 - ( a q ) 0.1 - 2 x ⇌ A g ( S 2 O 3 ) 2 3 - ( a q ) x + B r - x aq Here, K = K s p × K f = 25 K = x 2 ( 0.1 - 2 x ) 2 25 = x 2 ( 0.1 - 2 x ) 2 On solving x = 0.045 M.