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a 0.450 m solution of kcl needs to be prepared through dilution. a 2.00 m stock solution will be added to a 0.250 l volumetric flask and then water will be added to the 0.250 l mark. determine the volume (in ml) of the 2.00 m stock solution of kcl needed to produce this solution.

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CintiaSalazar

Taking into account the definition of dilution, the volume of the 2.00 M stock solution of KCl needed to produce the solution is 56.25 mL.

Dilution

When it is desired to prepare a less concentrated solution from a more concentrated one, it is called dilution. It is accomplished by simply adding more solvent to the solution at the same amount of solute.

The amount of solute does not change, but as more solvent is added, the concentration of the solute decreases, as the volume 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

Volume of the stock solution

In this case, you know:

  • Ci= 2 M
  • Vi= ?
  • Cf= 0.450 M
  • Vf= 0.250 L

Replacing in the definition of dilution:

2 M× Vi= 0.450 M× 0.250 L

Solving:

Vi= (0.450 M× 0.250 L)÷ 2 M

Vi= 0.05625 L= 56.25 mL (being 1 L= 1000 mL)

In summary, 56.25 mL of stock solution are needed.

Learn more about dilution:

brainly.com/question/28734745

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