Which two sets of reactants best represent the amphoteric character of `Zn(OH)_(2)`?
Set `1: Zn(OH)_(2) & OH^(-)(aq)`
Set `2: Zn(OH)_(2)(s)& H_(2)O(l)`
Set `3: Zn(OH)_(2)(s)&H^(+)(aq)`
Set `4: Zn(OH)_(2)(s)& NH_(3)(aq)`

Options

A. 1 and 2
B. 1 and 3
C. 2 and 4
D. 3 and 4

Explanation

To determine which two sets of reactants best represent the amphoteric character of `Zn(OH)_(2)`, we need to understand the definition of amphoteric compounds. Amphoteric compounds can react with both acids and bases, exhibiting both acidic and basic behavior.

### Step-by-Step Solution:

1. **Understanding Amphoteric Character**:
- Amphoteric compounds can react with acids to form salts and water, and they can also react with bases to form complex ions or other products.
- Zinc hydroxide, `Zn(OH)_(2)`, is known to be amphoteric.

2. **Analyzing the Given Sets**:
- **Set 1: `Zn(OH)_(2)` & `OH^(-)(aq)`**:
- Here, `Zn(OH)_(2)` can react with `OH^(-)` (a base). This reaction will lead to the formation of a complex ion, `Zn(OH)₄²⁻`. This shows the basic behavior of `Zn(OH)_(2)`.
- **Set 2: `Zn(OH)_(2)(s)` & `H_(2)O(l)`**:
- This set does not demonstrate any reaction, as water does not interact with `Zn(OH)_(2)` in a way that shows amphoteric behavior.
- **Set 3: `Zn(OH)_(2)(s)` & `H^(+)(aq)`**:
- In this case, `Zn(OH)_(2)` reacts with `H^+` (an acid) to form `Zn²⁺` and water. This shows the acidic behavior of `Zn(OH)_(2)`.
- **Set 4: `Zn(OH)_(2)(s)` & `NH_(3)(aq)`**:
- Ammonia is a weak base, and while it can interact with `Zn(OH)_(2)`, it does not clearly demonstrate the amphoteric nature as effectively as the other sets.

3. **Identifying the Correct Sets**:
- From the analysis, Set 1 (`Zn(OH)_(2)` & `OH^(-)(aq)`) shows the basic character of `Zn(OH)_(2)`.
- Set 3 (`Zn(OH)_(2)(s)` & `H^(+)(aq)`) shows the acidic character of `Zn(OH)_(2)`.
- Therefore, the two sets that best represent the amphoteric character of `Zn(OH)_(2)` are Set 1 and Set 3.

### Final Answer:
The correct sets that represent the amphoteric character of `Zn(OH)_(2)` are:
- **Set 1**: `Zn(OH)_(2)` & `OH^(-)(aq)`
- **Set 3**: `Zn(OH)_(2)(s)` & `H^(+)(aq)`