Home › If the degree of dissociation of a weak electrol…
If the degree of dissociation of a weak electrolyte increases while concentration is unchanged, which quantity in the relation $k_a = \dfrac{c\alpha^2}{1-\alpha}$ is directly affected by this increase?
A$k_a$ increases with larger $\alpha$ in the expression
B$k_a$ becomes zero because denominator decreases
C$\lambda_m^{\infty}$ must decrease to zero
DThe oxidation potential of zinc changes sign
Answer & Solution
Correct answer: A. $k_a$ increases with larger $\alpha$ in the expression
From the given formula, increasing $\alpha$ increases the numerator $\alpha^2$ and also decreases $1-\alpha$ in the denominator, so the value of the expression increases. The other options mix unrelated quantities or make incorrect claims.