Question
Given is a concentrated solution of a weak electrolyte A_xB_y of concentration 'c' and dissociation constant 'K'. The degree of dissociation is given by :
JEE Main
Chemistry
Ionic Equilibrium
2026
JEE Main 2026 (06 April Shift 2)
JEE Main Chemistry Question (2026) — Solution
Options
- A. [K c^ x+y-1 x^x y^y ]^ x+y
- B. ( K c^ x+y-1 x^x y^y )^ 1 x+y
- C. ( c^ x+y-1 x^x y^y K )^ x+y
- D. ( c^ x+y-1 x^x y^y K )^ 1 x+y
Answer
B. ( K c^ x+y-1 x^x y^y )^ 1 x+y
Step-by-step solution
The dissociation reaction of the weak electrolyte A_xB_y is: A_xB_y xA^ y+ + yB^ x- Initial concentrations: c 0 0 Equilibrium concentrations: c(1- ) cx cy The dissociation constant K is given by: K = [A^ y+ ]^x [B^ x- ]^y [A_xB_y] K = (cx )^x (cy )^y c(1- ) K = c^ x+y x^x y^y ^ x+y c(1- ) K = c^ x+y-1 x^x y^y ^ x+y 1- For a weak electrolyte, the degree of dissociation is very small, so 1- 1. K = c^ x+y-1 x^x y^y ^ x+y Solving for : ^ x+y = K c^ x+y-1 x^x y^y = ( K c^ x+y-1 x^x y^y )^ 1 x+y Answer: ( K c^ x+y-1 x^x y^y )^ 1 x+y
Related: Chemistry — Ionic Equilibrium · All PYQ Banks