Identify the reactant that is a Brønsted–Lowry acid and the reactant that is a Brønsted–Lowry base in each of the following:
a. HI(aq) + H₂O(l) → I^-(aq) + H₃O⁺(aq)

Verified step by step guidance

1. Step 1: Recall the definition of a Brønsted–Lowry acid and base. A Brønsted–Lowry acid is a substance that donates a proton (H⁺), while a Brønsted–Lowry base is a substance that accepts a proton (H⁺).
2. Step 2: Analyze the reactants in the given reaction: HI(aq) and H₂O(l). Determine which reactant donates a proton and which one accepts it.
3. Step 3: Observe that HI(aq) donates a proton (H⁺) to H₂O(l), forming I⁻(aq) and H₃O⁺(aq). This indicates that HI(aq) is the Brønsted–Lowry acid because it donates the proton.
4. Step 4: Recognize that H₂O(l) accepts the proton (H⁺) from HI(aq), forming H₃O⁺(aq). This indicates that H₂O(l) is the Brønsted–Lowry base because it accepts the proton.
5. Step 5: Conclude that in this reaction, HI(aq) is the Brønsted–Lowry acid, and H₂O(l) is the Brønsted–Lowry base.

Key Concepts

Brønsted–Lowry Acid

A Brønsted–Lowry acid is defined as a substance that donates a proton (H⁺) to another substance in a chemical reaction. In the given reaction, HI (hydroiodic acid) donates a proton to water, thus acting as the acid. This concept is fundamental in understanding acid-base reactions and their mechanisms.

Brønsted–Lowry Base

A Brønsted–Lowry base is a substance that accepts a proton in a chemical reaction. In the provided equation, water (H₂O) accepts a proton from HI, transforming into the hydronium ion (H₃O⁺). Recognizing the role of bases in proton transfer is crucial for analyzing acid-base reactions.

Proton Transfer Reaction

A proton transfer reaction is a type of chemical reaction where a proton is transferred from an acid to a base. This process is central to the Brønsted–Lowry theory of acids and bases, as it highlights the dynamic nature of acid-base interactions. Understanding this concept helps in predicting the products of such reactions and their implications in various chemical contexts.