Solutions, Acids, and Bases Online Practice

Question

Complete this assessment to review what you’ve learned. It will not count toward your grade.
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Question
Use the reaction to answer the question.

NH3 + H2O → OH– + NH4+

Which statement about the reaction is correct?

(1 point)
Responses

H2O is a base, and OH– is its conjugate acid.
H 2 O is a base, and OH – is its conjugate acid.

NH3 is a base, and NH4+ is its conjugate acid.
NH 3 is a base, and NH 4 + is its conjugate acid.

H2O is a base, and NH4+ is its conjugate acid.
H 2 O is a base, and NH 4 + is its conjugate acid.

NH3 is a base, and OH– is its conjugate acid.

Answer 1

In the given reaction:

NH3 + H2O → OH– + NH4+

We can analyze the roles of the reactants and products based on the Brønsted-Lowry acid-base theory. In this theory:

• A Brønsted-Lowry acid is a substance that donates a proton (H+).
• A Brønsted-Lowry base is a substance that accepts a proton (H+).

In this reaction:

• NH3 (ammonia) accepts a proton from H2O (water), making NH4+ (ammonium) the conjugate acid of NH3.
• H2O donates a proton to NH3, producing OH– (hydroxide), which is the conjugate base of H2O.

Now, let's evaluate the provided statements:

1. H2O is a base, and OH– is its conjugate acid.

   • Incorrect, because H2O is acting as an acid, and its conjugate base is OH–.

2. NH3 is a base, and NH4+ is its conjugate acid.

   • Correct, because NH3 accepts a proton to form NH4+, making NH4+ the conjugate acid of NH3.

3. H2O is a base, and NH4+ is its conjugate acid.

   • Incorrect, as H2O is not acting as a base but as an acid.

4. NH3 is a base, and OH– is its conjugate acid.

   • Incorrect, as OH– is the conjugate base of H2O, not the conjugate acid of NH3.

Thus, the correct statement about the reaction is:

NH3 is a base, and NH4+ is its conjugate acid.