To what volume (in mL) would you need to dilute 40.0 mL of a 1.25 M solution of NaCl to make a 0.0500 M solution of NaCl

1000 mL.

Explanation:

From the question given above, the following data were obtained:

Volume of stock solution (V1) = 40 mL

Molarity of stock solution (M1) = 1.25 M

Molarity of diluted solution (M2) = 0.05 M

Volume of diluted solution (V2) =...?

The volume of diluted solution can be obtained as shown below:

M1V1 = M1V1

1.25 × 40 = 0.05 × V2

50 = 0.05 × V2

Divide both side by 0.05

V2 = 50/0.05

V2 = 1000 mL

Therefore, the stock solution must be diluted to 1000 mL to obtain a 0.05 M solution of NaCl.