Chemistry · Ionic Equilibrium

JEE Main 2026 — 6 April, Evening Shift — Question 50

Given is a concentrated solution of a weak electrolyte Ax By\mathrm{A}_{x} \mathrm{~B}_{y} of concentration ' c ' and dissociation constant ' K '. the degree of dissociation is given by:

  1. Option A:

    [K×cx+y−1xxyy]x+y\left[K \times c^{x+y-1} x^{x} y^{y}\right]^{x+y}

  2. Option B:

    (Kcx+y−1xxyy)1x+y\left(\frac{K}{c^{x+y-1} x^{x} y^{y}}\right)^{\frac{1}{x+y}}

    Correct
  3. Option C:

    (cx+y−1xxyyK)x+y\left(\frac{c^{x+y-1} x^{x} y^{y}}{K}\right)^{x+y}

  4. Option D:

    (cx+y−1xxyyK)1x+y\left(\frac{c^{x+y-1} x^{x} y^{y}}{K}\right)^{\frac{1}{x+y}}

Answer: B

Step-by-step solution

AxBy⇌xAy++yBx−\mathrm{A}_{\mathrm{x}} \mathrm{B}_{\mathrm{y}} \rightleftharpoons \mathrm{xA}^{\mathrm{y}+}+\mathrm{yB}^{\mathrm{x}-} C(1−α)xCαyCα\mathrm{C}(1-\alpha) \quad \mathrm{xC} \alpha \quad \mathrm{yC} \alpha K=(xCα)x(xCα)yC(1−α)\mathrm{K}=\frac{(\mathrm{xC} \alpha)^{\mathrm{x}}(\mathrm{xC} \alpha)^{\mathrm{y}}}{\mathrm{C}(1-\alpha)} As α≪1⇒(1−α)≃1\alpha \ll 1 \Rightarrow(1-\alpha) \simeq 1 K=xxyyCx+y−1αx+yK=x^{x} y^{y} C^{x+y-1} \alpha^{x+y} α=(KCx+y−1xxyy)1x+y\alpha=\left(\frac{K}{C^{x+y-1} x^{x} y^{y}}\right)^{\frac{1}{x+y}}

Answer key and solution verified before publishing.

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Exam
JEE Main 2026
Subject
Chemistry
Chapter
Ionic Equilibrium
Topic
Fundamental Definitions
Given is a concentrated solution of a weak electrolyte A x B y of… | JEE Main 2026 PYQ with Solution · DhiX AI