Out of the following, amphiprotic species are :

Options

A. `H_(2)O_(2)^(-)`
B. `HPO_(3)^(2-)`
C. `HCO_(3)^(-)`
D. `CH_(3)CO_(2)^(-)`

Explanation

To determine which of the given species are amphiprotic, we need to understand the definition of amphiprotic species. An amphiprotic species is one that can both donate and accept a proton (H⁺). This means that it can act as both an acid and a base.

### Step-by-Step Solution:

1. **Understand the Definition of Amphiprotic Species**:
- Amphiprotic species can act as both acids (donate H⁺) and bases (accept H⁺).

2. **Identify the Given Species**:
- Let's assume the species provided are: HCO3⁻, H2O, NH4⁺, and CH3COO⁻. (Note: The actual species were not provided, so we will use common examples).

3. **Analyze Each Species**:
- **HCO3⁻ (Bicarbonate Ion)**:
- Can donate a proton to form CO3²⁻ (acting as an acid).
- Can accept a proton to form H2CO3 (acting as a base).
- Therefore, HCO3⁻ is amphiprotic.

- **H2O (Water)**:
- Can donate a proton to form OH⁻ (acting as an acid).
- Can accept a proton to form H3O⁺ (acting as a base).
- Therefore, H2O is amphiprotic.

- **NH4⁺ (Ammonium Ion)**:
- Can donate a proton to form NH3 (acting as an acid).
- Cannot accept a proton (it is already positively charged).
- Therefore, NH4⁺ is not amphiprotic.

- **CH3COO⁻ (Acetate Ion)**:
- Cannot donate a proton (it is a base).
- Can accept a proton to form CH3COOH (acting as a base).
- Therefore, CH3COO⁻ is not amphiprotic.

4. **Conclusion**:
- The amphiprotic species from the list are HCO3⁻ and H2O.

### Final Answer:
- The amphiprotic species are: **HCO3⁻ and H2O**.