Using the brønsted theory, classify the following as either an acid or a base by placing the compound in the correct bin.

Acid = donor (giver) proton (H + ion)

Base = acceptor (receiver) proton (H + ion)

Based on Bronsted-Lowry Theory, acid is an ion/molecule that acts as a proton donor (H +) to other ions/molecules. While bases are ions/molecules that act as proton acceptors (H +).

If an acid gives its proton (H +), then the rest of the acid can accept the proton and function as the conjugate base of the acid

Conversely, if a base is a proton acceptor (H +), then the ion/molecule formed can release the proton and function as a conjugate acid from that base. In general, these conjugate acid-base pairs can be described as follows:

Example

NH₃ (aq) + H₂O (l) ------> NH₄ + (aq) + OH– (aq)

Basa Asam Asam Basa

The acid-base conjugate pair is:

NH₃ and NH₄

H₂O and OH-

H₂O as an acid gives a proton to NH₃ so that it becomes NH₄ so that the remaining OH- as its conjugate base

While NH₃ as a base and NH₄ as a conjugate acid

Example 2:

HOCN + H₂O ------> H₃O⁺ + OCN⁻

The conjugate base of HOCN is OCN⁻ because OCN⁻ is the proton acceptor of H⁺ to form HOCN (as an acid)

the Bronsted-Lowry definition of an acid

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the Bronsted-Lowry definition of a base

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the acids and the bases in the chemical equation according to Bronsted-Lowry Theory

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Keywords: Bronsted-Lowry Theory, acid, base, proton, donor, acceptor, acid-base conjugate