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1 year ago

PLEASE ANSWER I AM BEGGING

Chemistry

1 answer:

TiliK225 [7]1 year ago

5 0

Taking into account the definition of dilution:

you have to use 8.23 mL of a stock solution of 7.00 M HNO₃ to prepare 0.120 L of 0.480 M HNO₃.
If you dilute 20.0 mL of the stock solution to a final volume of 0.270 L , the concentration of the diluted solution is 0.518 M.

<h3>Dilution</h3>

Dilution is the process of reducing the concentration of solute in solution, which is accomplished by simply adding more solvent to the solution at the same amount of solute.

In a dilution the amount of solute does not change, but as more solvent is added, the concentration of the solute decreases, as the volume (and weight) of the solution increases.

A dilution is mathematically expressed as:

Ci×Vi = Cf×Vf

where

Ci: initial concentration
Vi: initial volume
Cf: final concentration
Vf: final volume

<h3>Volume of stock solution</h3>

In this case, you know:

Ci= 7 M
Vi= ?
Cf= 0.480 M
Vf= 0.120 L

Replacing in the definition of dilution:

7 M× Vi= 0.480 M× 0.120 L

Solving:

Vi= (0.480 M× 0.120 L)÷ 7 M

<u><em>Vi= 0.00823 L= 8.23 mL</em></u> (being 1 L= 1000 mL)

Finally, you will need 8.23 mL of the stock solution.

<h3>Concentration of the diluted solution</h3>

In this case, you know:

Ci= 7 M assuming the stock solution is 7.00 M HNO₃
Vi= 20 mL= 0.02 L
Cf= ?
Vf= 0.270 L

Replacing in the definition of dilution:

7 M× 0.02 L= Cf× 0.270 L

Solving:

(7 M× 0.02 L)÷ 0.270 L= Cf

Finally, the concentration is 0.518 M.

Learn more about dilution:

brainly.com/question/13505906

brainly.com/question/6692004

brainly.com/question/11931563

brainly.com/question/16343005

brainly.com/question/24709069

#SPJ1

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