Understand that Ba(OH)_2 is a strong base and dissociates completely in water. Each formula unit of Ba(OH)_2 produces two hydroxide ions (OH⁻).
Calculate the concentration of hydroxide ions (OH⁻) in the solution. Since Ba(OH)_2 dissociates into two OH⁻ ions, the concentration of OH⁻ ions will be twice the concentration of Ba(OH)_2. Use the formula: [OH⁻] = 2 × [Ba(OH)_2].
Use the concentration of OH⁻ ions to find the pOH of the solution. The pOH is calculated using the formula: pOH = -log[OH⁻].
Convert the pOH to pH. Remember that pH and pOH are related by the equation: pH + pOH = 14. Use this relationship to find the pH: pH = 14 - pOH.
Review the calculated pH value and compare it to the given options to ensure it matches one of the provided answers.