A chemist makes 940. mL of sodium carbonate (Na_2CO_3) working solution by adding distilled water to 200. mL of a 0.171 m stock solution of sodium carbonate in water. Calculate the concentration of the chemist's working solution. Round your answer to 3 significant digits.

Question

Chemistry

Pamela Casey

6 January, 06:10

A chemist makes 940. mL of sodium carbonate (Na_2CO_3) working solution by adding distilled water to 200. mL of a 0.171 m stock solution of sodium carbonate in water. Calculate the concentration of the chemist's working solution. Round your answer to 3 significant digits.

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Answers (1)

Know the Answer?

Karissa Harmon · Answer 1

The answer is 0.0698 M

Explanation:

The concentration was prepared by a serial dilution method.

The formula for the preparation I M1V1 = M2V2

M1 = the concentration of the stock solution = 0.171 M

V1 = volume of the stock solution taken = 200 mL

M2 = the concentration produced

V2 = the volume of the solution produced = 940 mL

Substitute these values in the formula

0.171 * 200 = 490 * M2

34.2 = 490 * M2

Make M2 the subject of the formula

M2 = 34.2/490

M2 = 0.069795

M2 = 0.0698 M (3 s. f)

The concentration of the Chemist's working solution to 3 significant figures is 0.0698M