The basicity of an acid is defined as

Options

A. the number of replaceable OH-ions
B. the number of `H^+` ions that can be formed from the acid
C. the power of the acid to form salts
D. none of the above

Answer

**Step-by-Step Solution:**

1. **Understanding Basicity**: Basicity of an acid refers to the number of hydrogen ions (H⁺) that can be released or replaced by the acid in a solution. This is a key concept in acid-base chemistry.

2. **Definition of Basicity**: Basicity can be defined as the number of replaceable H⁺ ions in an acidic solution. It indicates how many H⁺ ions an acid can donate when dissolved in water.

3. **Examples of Acids**:
- **Sulfuric Acid (H₂SO₄)**: This acid can dissociate into two H⁺ ions and one sulfate ion (SO₄²⁻). Therefore, it has a basicity of 2 because it can release 2 H⁺ ions.
- **Acetic Acid (CH₃COOH)**: When this acid dissociates, it produces one H⁺ ion and one acetate ion (CH₃COO⁻). Thus, its basicity is 1 since it can release only 1 H⁺ ion.
- **Hydrochloric Acid (HCl)**: This acid also dissociates to give one H⁺ ion and one chloride ion (Cl⁻). Hence, the basicity of HCl is 1.

4. **Conclusion**: The basicity of an acid is determined by the number of H⁺ ions it can produce in a solution. For example, H₂SO₄ has a basicity of 2, while both CH₃COOH and HCl have a basicity of 1.

5. **Final Answer**: Therefore, the basicity of an acid is defined as the number of H⁺ ions that can be formed from the acid.

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