Which are correct for the following reaction?
`[Cu(H_(2)O)_(3) OH]^(+) [Al(H_(2)O)_(6)]^(3)to[Cu(H_(2)O)_(4)]^(2+) + [Al(H_(2)O)_(5) OH]^(2+)`

Options

A. A is base and B is acid
B. C is conjugate acid of A
C. B is conjugate acid of D
D. B is conjugate base of D

Answer

To analyze the given reaction and determine which statements are correct, we will break down the reaction step by step.

### Given Reaction:
\[ [Cu(H_2O)_3OH]^+ + [Al(H_2O)_6]^{3+} \rightarrow [Cu(H_2O)_4]^{2+} + [Al(H_2O)_5OH]^{2+} \]

### Step 1: Identify the Species
- **A**: \([Cu(H_2O)_3OH]^+\)
- **B**: \([Al(H_2O)_6]^{3+}\)
- **C**: \([Cu(H_2O)_4]^{2+}\)
- **D**: \([Al(H_2O)_5OH]^{2+}\)

### Step 2: Analyze the Reaction
1. **A to C**:
- The conversion from A to C involves the loss of a proton (H⁺) from the hydroxyl group (OH) in A.
- This means that A is acting as a base because it accepts a proton to form C.

2. **B to D**:
- The conversion from B to D involves the release of a proton (H⁺) from B.
- This indicates that B is acting as an acid because it donates a proton to form D.

### Step 3: Identify Conjugate Acid-Base Pairs
- **For A and C**:
- A is a base and C is its conjugate acid.

- **For B and D**:
- B is an acid and D is its conjugate base.

### Step 4: Verify the Statements
1. **Option 1**: A is a base.
- **Correct**: A accepts a proton to form C.

2. **Option 2**: C is the conjugate acid of A.
- **Correct**: C is formed when A accepts a proton.

3. **Option 3**: B is the conjugate acid of D.
- **Correct**: B donates a proton to form D, making B the conjugate acid of D.

4. **Option 4**: B is the conjugate base of D.
- **Incorrect**: B is an acid, and D is its conjugate base.

### Conclusion
The correct statements are:
- Option 1: Correct
- Option 2: Correct
- Option 3: Correct
- Option 4: Incorrect

Thus, the answer is that Options 1, 2, and 3 are correct.

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