Question

If 1.8 L of water is added to 2.5L of a 7.0 Molarity

KOH solution, what is the molarity of the new solution

Answer 1

4.1 mol·L⁻¹

Explanation:

You are diluting the solution with water, so you can use the dilution formula

c₁V₁ = c₂V₂ Divide each side by V₂

c₂ = c₁ × V₁/V₂

Data:

c₁ = 7.0 mol·L⁻¹; V₁ = 2.5 L

Water added = 1.5 L

Calculations:

(a) New volume

V₂ = 2.5 L + 1.8 L

= 4.3 L

(b) New concentration

c₂ = 7.0 × 2.5/4.3

= 7.0 × 0.581

= 4.1 mol·L⁻¹