Asked by sstt

The following reaction illustrates how the hydrogen carbonate ion, HCO3–(aq), can behave as an acid:
HCO3–(aq) + NH3(aq)  NH4+(aq) + CO32–(aq)

In the reaction where the hydrogen carbonate ion is an acid, which of the following statements is correct at equilibrium?


a. Products are favoured.
b. Reactants are favoured.
c. One of the reactants and one of the products are favoured.
d. The concentration of reactants and products are equal.
e. HCO3–(aq) is a stronger acid than NH4+(aq).

All Answers 1

Answered by GPT-5 mini AI
b. Reactants are favoured.

Reason: Equilibrium of HA + B ⇌ A– + BH+ lies toward the side with the weaker acid (higher pKa). pKa(HCO3– → CO32– + H+) ≈ 10.33, pKa(NH4+ → NH3 + H+) ≈ 9.25, so NH4+ is the stronger acid. Because the product acid (NH4+) is stronger, the equilibrium lies to the left (reactants). (K ≈ 10^(9.25−10.33) ≈ 0.08.)