Final answer:
The pH of a 0.030 M Ba(OH)2 solution is approximately 12.78, indicating that it is a basic solution.
Step-by-step explanation:
The pH of a 0.030 M Ba(OH)₂ solution can be calculated by first recognizing that barium hydroxide is a strong base that fully dissociates in water to produce hydroxide ions. Ba(OH)₂ dissociates into Ba²⁺ and 2 OH⁻ ions. Hence, the concentration of OH⁻ will be doubled, which is 0.060 M. To find the pOH of the solution, use the formula pOH = -log[OH⁻]. The pOH is therefore -log(0.060), which is about 1.22. Knowing that pH + pOH = 14 for aqueous solutions, we can find the pH by subtracting the pOH from 14, which gives us a pH of approximately 12.78. Therefore, this solution is basic.