The pH of `0.25 M Ba(OH)_2` solution is:

Explanation

To calculate the pH of a 0.25 M Ba(OH)₂ solution, follow these steps:

### Step 1: Understand the dissociation of Ba(OH)₂
Barium hydroxide, Ba(OH)₂, dissociates in water to produce barium ions (Ba²⁺) and hydroxide ions (OH⁻):
\[ \text{Ba(OH)}_2 \rightarrow \text{Ba}^{2+} + 2 \text{OH}^- \]

### Step 2: Calculate the concentration of OH⁻ ions
From the dissociation equation, we see that 1 mole of Ba(OH)₂ produces 2 moles of OH⁻ ions. Therefore, if we have a 0.25 M solution of Ba(OH)₂:
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