A strong acid is titrated with weak base. At equivalence point, pH will be :

Options

A. ` lt 7`
B. `gt 7`
C. 0
D. Cannot predict

Explanation

To determine the pH at the equivalence point when a strong acid is titrated with a weak base, we can follow these steps:

### Step 1: Understand the nature of the reactants
- A strong acid completely dissociates in solution to produce a high concentration of hydrogen ions (H⁺).
- A weak base only partially dissociates in solution, producing a lower concentration of hydroxide ions (OH⁻).

### Step 2: Identify the pH of the strong acid
- The pH of a strong acid is typically less than 3 or 4 due to the high concentration of H⁺ ions.

### Step 3: Consider the reaction at the equivalence point
- At the equivalence point, all the strong acid has reacted with the weak base. The resulting solution will contain the conjugate acid of the weak base.
- This conjugate acid will partially dissociate in water, producing H⁺ ions.

### Step 4: Determine the pH at the equivalence point
- Since the solution contains a conjugate acid from the weak base, it will contribute to an increase in H⁺ concentration.
- Therefore, the pH at the equivalence point will be less than 7 because the solution remains acidic due to the presence of the strong acid and the conjugate acid.

### Conclusion
- The pH at the equivalence point when titrating a strong acid with a weak base will be less than 7.

### Final Answer
The pH at the equivalence point will be **less than 7**.

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