When 0.5 mole of NaOH was added to one litre of a buffer solution, its pH changed 5.70 to 5.85. Find the buffer capacity.

Explanation

To find the buffer capacity of the solution after adding 0.5 moles of NaOH, we can follow these steps:

### Step 1: Understand Buffer Capacity
Buffer capacity is defined as the amount of acid or base that can be added to a buffer solution before a significant change in pH occurs. It can be mathematically expressed as:
\[ \text{Buffer Capacity} = \frac{\text{Number of moles of acid or base added}}{\text{Change in pH}} \]

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