Question

A student has 100. mL of 0.400 M CuSO4 (aq) and is asked to make 100. mL of 0.150 M CuSO4 (aq) for a spectrophotometry experiment. The following laboratory equipment is available for preparing the solution: centigram balance, weighing paper, funnel, 10 mL beaker, 150 mL beaker, 50 mL graduated cylinder, 100 mL volumetric flask, 50 mL buret, and distilled water.
Calculate the volume of 0.400 M CuSO4(aq) required for the preparation

Answer 1

Answer:

We have to take 37.5 mL of a 0.400 M solution

Explanation:

Step 1: Data given

Stock volume = 100 mL  = 0.100L

Stock concentration 0.400 M

Volume of solution he wants to make = 100 mL = 0.100L

Concentration of solution he wants to make = 0.150 M

Step 2: Calculate the volume of 0.400 M CuSO4 needed

C1*V1 = C2*V2

⇒with C1 = the stock concentration = 0.400M

⇒with V1 = the volume of the stock = TO BE DETERMINED

⇒with C2 = the concentration of the solution he wants to make = 0.150 M

⇒with V2 = the volume of the solution made = 0.100 L

0.400 M * V1 = 0.150M * 0.100L

V1 = (0.150M*0.100L) / 0.400 M

V1 = 0.0375 L = 37.5 mL

We have to take 37.5 mL of a 0.400 M solution

Answer 2

Answer:

37.5 mL

Explanation:

Step 1:

Data obtained from the question.

Concentration of the stock solution (C1) = 0.4M

Volume of stock solution needed (V1) =?

Concentration of diluted solution (C2) = 0.150 M

Volume of diluted solution (V2) = 100 mL

Step 2:

Determination of the volume of the stock solution needed to produce 100 mL of 0.150 M CuSO4.

This is illustrated below:

With the application of the diluted equation, the volume of the stock solution needed can be obtained as follow:

C1V1 = C2V2

0.4 x V1 = 0.150 x 100

Divide both side by 0.4

V1 = (0.150 x 100)/0.4

V1 = 37.5 mL

Therefore, 37.5 mL of the stock solution i.e 0.400 M CuSO4(aq) required for the preparation.