Name a species which can act as both conjugate acid and conjugate base and explain how ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Conjugate Acids and Bases:**
- According to the Bronsted-Lowry theory, an acid is a species that donates a proton (H⁺), while a base is a species that accepts a proton. When an acid donates a proton, it forms its conjugate base. Conversely, when a base accepts a proton, it forms its conjugate acid.

2. **Identifying a Species that Acts as Both:**
- A common species that can act as both a conjugate acid and a conjugate base is **dihydrogen phosphate (H₂PO₄⁻)**.

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