In the reaction: `[Cu(H_(2)O)_(3)(OH)]^(+) + [AI(H_(2)O)_(6)]^(3+) to [Cu(H_(2)O)_(4)]^(2+) + [AI(H_(2)O)_(5)(OH)]^(2+)`

Options

A. C is the conjugate acid of A and D is the conjugate base of B
B. A is an acid and B is the base
C. A is a base and B is the salt
D. C is the conjugate base of A and D is the conjugate acid of B

Answer

To solve the given reaction step by step, we need to identify the acids, bases, and their conjugates in the reaction:

**Reaction:**
\[ [Cu(H_2O)_3(OH)]^+ + [Al(H_2O)_6]^{3+} \rightarrow [Cu(H_2O)_4]^{2+} + [Al(H_2O)_5(OH)]^{2+} \]

### Step 1: Identify the Reactants and Products
- **Reactants:**
- \([Cu(H_2O)_3(OH)]^+\) - This is a copper complex with three water molecules and one hydroxide ion.
- \([Al(H_2O)_6]^{3+}\) - This is an aluminum complex with six water molecules.

- **Products:**
- \([Cu(H_2O)_4]^{2+}\) - This is a copper complex with four water molecules.
- \([Al(H_2O)_5(OH)]^{2+}\) - This is an aluminum complex with five water molecules and one hydroxide ion.

### Step 2: Determine Acid-Base Behavior
- In this reaction, we can see that \([Cu(H_2O)_3(OH)]^+\) donates a proton (H\(^+\)) to \([Al(H_2O)_6]^{3+}\).
- Therefore, \([Cu(H_2O)_3(OH)]^+\) acts as the **acid** and \([Al(H_2O)_6]^{3+}\) acts as the **base**.

### Step 3: Identify Conjugate Acids and Bases
- After donating a proton, \([Cu(H_2O)_3(OH)]^+\) becomes \([Cu(H_2O)_4]^{2+}\). Thus, \([Cu(H_2O)_4]^{2+}\) is the **conjugate base** of \([Cu(H_2O)_3(OH)]^+\).
- \([Al(H_2O)_6]^{3+}\) accepts a proton and becomes \([Al(H_2O)_5(OH)]^{2+}\). Thus, \([Al(H_2O)_5(OH)]^{2+}\) is the **conjugate acid** of \([Al(H_2O)_6]^{3+}\).

### Step 4: Write the Final Relationships
- **Acid-Base Pairs:**
- Acid: \([Cu(H_2O)_3(OH)]^+\) → Conjugate Base: \([Cu(H_2O)_4]^{2+}\)
- Base: \([Al(H_2O)_6]^{3+}\) → Conjugate Acid: \([Al(H_2O)_5(OH)]^{2+}\)

### Conclusion
In summary, the reaction involves the transfer of a proton from the copper complex to the aluminum complex, resulting in the formation of the respective conjugate acid and base pairs.

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