Question

Two stock solutions will be provided : 1. ~ 2.00 × 10 -5 M quinine sulfate dihydrate in ~ 1.0 M H2SO4 2. ~ 0.150 M KCl

In this stock solution, tell me how to calculate Dilute the stock solutions to make 5 samples with different concentrations of Cl- in the range of 0.0- 0.04 M Concentration of quinine sulfate dihydrate should be near 1.00 × 10-5 M and needs to be the same for all samples Concentration of H2SO4 should be ~ 0.5 M

explain me with equations thank youu

Answer 1

The concentrations of the stock solutions are:

1. Quinine sulfate dihydrate, 2.00*10-5 M; H2SO4, 1.0 M

2. KCl, 0.150 M.

The five solutions prepared will have the following concentrations.

1. Quinine sulfate dehydrate, 1.00*10-5 M; H2SO4, 0.5 M

2. KCl, 0.00 M, 0.01 M, 0.02 M, 0.03 M and 0.04 M.

Let use first dilute the first reagent and prepare 500 mL solution.

Use the dilution equation:

M1*V1 = M2*V2

where M1 = molarity of stock solution;

V1 = volume of stock solution;

M2 = molarity of the reagent in the prepared solution

and V2 = final volume of the prepared solution.

Quinine sulfate dihydrate:

Plug in values.

(2.00*10-5 M)*V1 = (1.00*10-5 M)*(500 mL)

====> V1 = 250 mL.

H2SO4:

(1.0 M)*V1 = (0.5 M)*(500 mL)

====> V1 = 250 mL.

Mix 250 mL of 2.00*10-5 M quinine sulfate dehydrate with 250 mL of 1.0 M H2SO4 to prepare the reagent solution A. Reagent solution A has 1.00*10-5 M quinine sulfate dehydrate and 0.5 M H2SO4.

Next prepare 150 mL each of the five solutions where we have varying concentrations of KCl.

Use the dilution equation:

0.00 M Cl-:

(0.150 M)*V1 = (0.00 M)*(150 mL)

=====> V1 = 0.00 mL.

0.01 M Cl-:

(0.150 M)*V1 = (0.01 M)*(150 mL)

=====> V1 = 10.00 mL.

0.02 M Cl-:

(0.150 M)*V1 = (0.02 M)*(150 mL)

=====> V1 = 20.00 mL.

0.03 M Cl-:

(0.150 M)*V1 = (0.03 M)*(150 mL)

=====> V1 = 30.00 mL.

0.04 M Cl-:

(0.150 M)*V1 = (0.04 M)*(150 mL)

=====> V1 = 40.00 mL.

The five solutions are prepared by adding 0.00 mL, 10.00 mL, 20.00 mL, 30.00 mL and 40.00 mL solutions of 0.150 M KCl with 100.00 mL, 90.00 mL, 80.00 mL, 70.00 mL and 60.00 mL of Reagent A.