Question

If I add 25 mL of water to 125 mL of a 0.15 M NaOH solution, what will the molarity of the diluted solution be? (convert mL to L and round answer to 3 decimals)

Answer 1

0.125 M

Step-by-step explanation:

M₁V₁ = M₂V₂

125 mL / 1000 = 0.125 L = V₁

25 + 125 = 150 mL / 1000 = 0.150 L = V₂

0.15 M = M₁

M₁ × V₁ / V₂ = M₂

(0.15) × (0.125) / (0.150) = 0.125 M

0.125 M is the answer

Answer 2

0.75 M

Step-by-step explanation:

M1 = 0.15 M

V1 = 125 mL or 0.125 L

M2 = Y

V2 = 25 mL or 0.025 L

0.15 M x 0.125 mL = Y x 0.025 L

Y = 0.15 M x 0.125 mL / 0.025 L

Cancel out the mL

Y = 0.01875M / 0.025 L

Y = 0.75M