Question

Calculate the volume of 1 M NaOH needed to prepare 12.0 mL of a 0.10-M solution. Prepare this solution. (Refer to the Dilutions section in the Background.)

Answer 1

Answer:

1.2 mL

Explanation:

This is a problem of simple dilution. The dilution principle simply agrees that the number of moles before dilution must be equal to the number of moles after dilution.

Recall that: number of moles = mass/molar mass or molarity x volume.

Hence, for the dilution principle:

              initial molarity x initial volume = final molarity x final volume.

In this case, initial molarity of NaOH = 1 M, initial volume = ?, final molarity = 0.1 M, final volume = 12.0 mL.

Initial volume = final molarity x final volume/initial molarity

                       = 0.1 x 12/1 = 1.2 mL

It thus means that 1.2 mL of 1 M NaOH would be taken and then diluted up to 12.0 mL mark by the addition of distilled water in order to produce 12.0 mL, 0.10 M NaOH solution.