How many moles of `Ca(OH)_(2)` must be dissolved to produce 250 mL of an aqueous solution of pH `10.65`, assuming completer dissociation ?

Explanation

To find out how many moles of \( \text{Ca(OH)}_2 \) must be dissolved to produce 250 mL of an aqueous solution with a pH of 10.65, we can follow these steps:

### Step 1: Calculate the pOH
The pH of the solution is given as 10.65. We can calculate the pOH using the relationship:
\[ \text{pOH} = 14 - \text{pH} \]
Substituting the value of pH:
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