Question

How much 0.20M NaCl solution would you need to prepare 250 mL of a 0.15 M solution?

Answer 1

use dilution formula

M1*V1 = M2*V2

Here:

M1 is molarity of solution before dilution

M2 is molarity of solution after dilution

V1 is volume of solution before dilution

V2 is volume of solution after dilution

we have:

M1 = 0.2 M

M2 = 0.15 M

V2 = 250.0 mL

we have below equation to be used:

M1*V1 = M2*V2

V1 = (M2 * V2) / M1

V1 = (0.15*250)/0.2

V1 = 187.5 mL

Answer: 187.5 mL