O SX10 E 251 x 1014 4 Pick the strongest base from the foll

O : SX10 E 2.51 x 10-14 4. Pick the strongest base from the following list. A. PO43-(H3PO4: Kal-7.5 × 10\". Ke-62x 10-s, Ka3 = 4.2x 10-13) weak E. NOK, for HF = 6.6 x10-4) weak stray bee

Solution

we know,

stronger acid have weaker conjugate base and vice versa.

when Ka increases that means acidity increases. High Ka value means higher is acidity.

Ka of HPO₄^2- is 4.2 * 10^-13.

so HPO₄^2- is weakest acid and it conjugate base PO₄^3- is trongest base.

option A is the answer.