To solve this problem, we’ll use the dilution formula:
M₁V₁ = M₂V₂
where:
- M₁ is the initial molarity of the concentrated solution (0.5 M NaOH)
- V₁ is the initial volume of the concentrated solution (what we want to find)
- M₂ is the final molarity of the diluted solution (0.1 M NaOH)
- V₂ is the final volume of the diluted solution (10 L)
Rearranging the formula to solve for V₁:
V₁ = (M₂V₂) / M₁
Substituting the given values:
V₁ = (0.1 M * 10 L) / 0.5 M
Calculating V₁:
V₁ = 2 L
Therefore, 2 liters of 0.5 M NaOH is required to prepare a 10 L solution of 0.1 M NaOH.