Question

Hydrochloric acid is the primary component of gastric juice in the stomach (see Chemistry in Action: GERD-Too Much Acid or Not Enough? on p. 299 in the textbook). The reaction between hydrochloric acid and the carbonate ion, the primary active ingredient in antacid tablets such as TUMS®,can be written as HCl(aq)+CO2−3(aq)⇌HCO−3(aq)+Cl−(aq)

Answer 1

Answer:

Acid: HCl(aq), conjugate base: Cl⁻(aq)

Base: CO₃⁻²(aq), conjugate acid: HCO₃⁻(aq)

The rewrite reaction is shown below.

Explanation:

The acid compound is the one that loses an H⁺, and the compound formed when it happens is its conjugate base. The base compound is the acceptor of H⁺, and its conjugate acid is the compound formed (Brosted-Lowry theory).

So, the acid-base pairs are:

Acid: HCl(aq), conjugate base: Cl⁻(aq)

Base: CO₃⁻²(aq), conjugate acid: HCO₃⁻(aq)

The TUMS® is an antacid, so it intends to reduce the concentration of the strong acid HCl. So, the forward reaction is favored. It can be represented with the forward arrow larger than the reversible arrow, as shown in the image below.