JEE Main 2022 · 25 Jul · Shift 2 · Chemistry Q63

ChemistrySingle correct+4 / -1Question 63 of 90

$K_{a_1}$ , $K_{a_2}$ and $K_{a_3}$ are the respective ionization constants for the following reactions (a), (b), and (c).

(a) $\mathrm{H_2C_2O_4\rightleftharpoons H^++HC_2O_4^-}$

(b) $\mathrm{HC_2O_4^-\rightleftharpoons H^++C_2O_4^{2-}}$

The relationship between $K_{a_1}$ , $K_{a_2}$ and $K_{a_3}$ is given as

K_{a_3}=K_{a_1}+K_{a_2}

K_{a_3}=K_{a_1}-K_{a_2}

K_{a_3}=K_{a_1}/K_{a_2}

K_{a_3}=K_{a_1}\times K_{a_2}

Answer and worked solution

Official answer: D

Adding reactions (a) and (b) gives (c), so $K_{a_3}=K_{a_1}K_{a_2}$ .

(D)

Topics:Acids and bases Law of mass action and Kc, Kp

JEE Main 2022 · 25 Jul · Shift 2, Chemistry question 63