Chemistry · EQUILIBRIUM

Given below are statements regarding polyprotic acids and factors affecting acid strength: (A) Higher order ionization constants (\( K_{a_2}, K_{a_3} \)) are smaller than the lower order ionization constant (\( K_{a_1} \)). (B) Down a group in the periodic table, the H-A bond strength decreases as the size of atom A increases. (C) Across a period, the acid strength decreases from \( \text{CH}_4 \) to \( \text{HF} \). (D) In a polyprotic acid solution, the primary reaction producing \( \text{H}_3\text{O}^+ \) ions is the first ionization step. Choose the correct answer from the options given below:

1. A
   (A), (C) and (D) only
2. B
   (A), (B) and (D) only
3. C
   (B) and (C) only
4. D
   (A) and (C) only