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Chemistry · EQUILIBRIUM
हिन्दीConsider the following statements regarding the ionization of weak acids and bases: (A) Larger value of \( K_a \) indicates a stronger acid. (B) For a weak acid \( \text{HX} \), \( K_a = \frac{c\alpha^2}{1-\alpha} \), where \( \alpha \) is the degree of ionization. (C) As the initial concentration \( c \) of a weak acid decreases, its degree of ionization \( \alpha \) also decreases. (D) At 298 K, the ionization constant \( K_b \) of ammonia is \( 1.77 \times 10^{-5} \). Which of the above statements are correct?
Correct answer · Option 2
(A), (B) and (D) only
Explanation
(A), (B), and (D) are correct. (C) is incorrect because by Ostwald's dilution law, the degree of ionization \( \alpha \approx \sqrt{K_a/c} \) increases upon dilution (decreasing concentration).
