Final answer:
The acids in the given reaction are HCl, a strong acid, and H₂SO₃, a weak acid. The reaction will proceed in the direction that forms the weaker acid, H₂SO₃, meaning the correct option is (d) H₂SO₃.
Step-by-step explanation:
In the given reaction, HCO₂Na(aq) + HCl (aq) → NaCl (aq) + H₂SO₃(aq), the acids present are HCl and H₂SO₃. Hydrochloric acid (HCl) is known to be a strong acid, completely ionizing in water, whereas sulfurous acid (H₂SO₃) is a weak acid and does not completely ionize in solution. Therefore, by understanding acid strength, the reaction will proceed in the direction that favors the formation of the weaker acid and base, according to Le Châtelier’s principle.
So, in the completion of the reaction, we witness the conversion from a stronger to a weaker acid, which implies the reaction will proceed towards the right, forming H₂SO₃ and NaCl. Thus, between the options given, (a) Cl, (b) HCl, (c) HCO₃Na, and (d) H₂SO₃, the correct option is (d) H₂SO₃.