Ionisation is a …………………… process.

Options

A. irreversible
B. reversible
C. Both (a) and (b)
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Understanding Ionization**: Ionization is the process by which a compound dissociates into ions. This can occur in both weak and strong electrolytes.

2. **Weak Electrolytes**: Weak electrolytes partially dissociate into ions when dissolved in water. For example, acetic acid (CH₃COOH) is a weak electrolyte that only partially ionizes to form CH₃COO⁻ and H⁺ ions. This process is reversible, meaning the ions can recombine to form the original compound.

3. **Strong Electrolytes**: Strong electrolytes, on the other hand, completely dissociate into ions in solution. An example is hydrochloric acid (HCl), which fully ionizes to form H⁺ and Cl⁻ ions. This process is irreversible because once the compound has dissociated, it does not recombine under normal conditions.

4. **Conclusion**: Therefore, ionization can be classified as both a reversible process (in the case of weak electrolytes) and an irreversible process (in the case of strong electrolytes).

5. **Final Answer**: Ionization is a **reversible and irreversible process**.

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