Answered

In the following reaction:

[tex]\[ HCO_3^{-}(aq) + H_2O(l) \rightarrow H_2CO_3(aq) + OH^{-}(aq) \][/tex]

A. [tex]\( H_2O \)[/tex] is an acid and [tex]\( HCO_3^{-} \)[/tex] is its conjugate base.
B. [tex]\( HCO_3^{-} \)[/tex] is an acid and [tex]\( H_2CO_3 \)[/tex] is its conjugate base.
C. [tex]\( HCO_3^{-} \)[/tex] is an acid and [tex]\( OH^{-} \)[/tex] is its conjugate base.
D. [tex]\( H_2O \)[/tex] is an acid and [tex]\( OH^{-} \)[/tex] is its conjugate base.
E. [tex]\( H_2O \)[/tex] is an acid and [tex]\( H_2CO_3 \)[/tex] is its conjugate base.



Answer :

GinnyAnswer
Let's carefully analyze the given chemical reaction and identify the acids and bases along with their conjugate pairs:

[tex]$ HCO _3^{-}(a q)+ H _2 O (l) \rightarrow H _2 CO _3(a q)+ OH ^{-}(a q) $[/tex]

In this reaction:

1. Identify acids and bases based on proton transfer:
- An acid donates a proton ([tex]\( H^+ \)[/tex]).
- A base accepts a proton ([tex]\( H^+ \)[/tex]).

2. Identify the conjugate acid-base pairs:
- The conjugate base is what remains after an acid donates a proton.
- The conjugate acid is what forms when a base accepts a proton.

### Step-by-step analysis:

- Water ([tex]\( H_2O \)[/tex]):
- In this reaction, water behaves as an acid. It donates a proton ([tex]\( H^+ \)[/tex]) to form hydroxide ion ([tex]\( OH^- \)[/tex]).
- So, [tex]\( H_2O \)[/tex] (acid) → [tex]\( OH^- \)[/tex] (conjugate base).

- Bicarbonate ion ([tex]\( HCO_3^- \)[/tex]):
- In this reaction, the bicarbonate ion behaves as a base. It accepts a proton ([tex]\( H^+ \)[/tex]) to form carbonic acid ([tex]\( H_2CO_3 \)[/tex]).
- So, [tex]\( HCO_3^- \)[/tex] (base) → [tex]\( H_2CO_3 \)[/tex] (conjugate acid).

Summarizing the pairs:
- [tex]\( H_2O \)[/tex] (acid) and [tex]\( OH^- \)[/tex] (conjugate base).
- [tex]\( HCO_3^- \)[/tex] (base) and [tex]\( H_2CO_3 \)[/tex] (conjugate acid).

Now, let's examine each statement:

1. [tex]\( H_2O \)[/tex] is an acid and [tex]\( HCO_3^- \)[/tex] is its conjugate base.
- Incorrect. [tex]\( H_2O \)[/tex] is an acid in this reaction, but its conjugate base is [tex]\( OH^- \)[/tex].

2. [tex]\( HCO_3^- \)[/tex] is an acid and [tex]\( H_2CO_3 \)[/tex] is its conjugate base.
- Incorrect. [tex]\( HCO_3^- \)[/tex] is a base, and [tex]\( H_2CO_3 \)[/tex] is its conjugate acid.

3. [tex]\( HCO_3^- \)[/tex] is an acid and [tex]\( OH^- \)[/tex] is its conjugate base.
- Incorrect. [tex]\( HCO_3^- \)[/tex] is a base, and [tex]\( OH^- \)[/tex] is not related to [tex]\( HCO_3^- \)[/tex] as a conjugate pair.

4. [tex]\( H_2O \)[/tex] is an acid and [tex]\( OH^- \)[/tex] is its conjugate base.
- Correct. [tex]\( H_2O \)[/tex] acts as an acid in this reaction and [tex]\( OH^- \)[/tex] is the conjugate base.

5. [tex]\( H_2O \)[/tex] is an acid and [tex]\( H_2CO_3 \)[/tex] is its conjugate base.
- Incorrect. [tex]\( H_2CO_3 \)[/tex] is not the conjugate base of [tex]\( H_2O \)[/tex]. [tex]\( H_2CO_3 \)[/tex] is formed from [tex]\( HCO_3^- \)[/tex].

Thus, the correct statement is:

[tex]\( H_2O \)[/tex] is an acid and [tex]\( OH^- \)[/tex] is its conjugate base.