What is the pH of the resulting solution?

Question

A solution is made by dissolving 0.06600 moles of Ba(OH)₂ in enough water to make 260.0 mL of solution. What is the pH of the resulting solution?

Answer 1

The pH is 13.706

Given:

0.06600 moles of Ba(OH)₂

260 mL of solution or .260 L

In 1 mole of Ba(OH)₂ there is 2 moles of OH

so in 0.06600 moles of Ba(OH)₂ there is 0.132 moles of OH ( 2*0.06600 = 0.132)

Calculate concentration: Moles/Volume

0.132 moles of OH / .260 L of solution = .508 M = [OH-]

Calculate pOH :

pOH = -log[OH-]

-log [.508] = 0.294 = pOH

Calculate pH:

pH + pOH = 14

pH = 14- pOH

pH= 14 - (0.294)

pH= 13.706