Perchloric acid is strongest acid, but weakest oxidising agent. Why? 

Explanation

**Step-by-Step Solution:**

1. **Understanding Perchloric Acid**:
- Perchloric acid has the chemical formula HClO₄. It is known as a strong acid due to its complete ionization in water.

2. **Ionization of Perchloric Acid**:
- When perchloric acid ionizes, it dissociates into ClO₄⁻ (perchlorate ion) and H⁺ (hydrogen ion):
\[
...