contestada

A chemist needs to create a series of standard Cu2 (aq) solutions for an absorbance experiment. For the first standard, he uses a pipet to transfer 25.00 mL of a 2.96 M Cu2 (aq) stock solution to a 250.0 mL volumetric flask and adds enough water to dilute to the mark. He then uses a second pipet to transfer 20.00 mL of the second solution to a 100.0 mL volumetric flask and adds enough water to dilute to the mark. Calculate the concentration of the Cu2 (aq) solution in the 100.0 mL volumetric flask.

Respuesta :

mauricioalessandrell

Answer:

The concentration of the Cu2 in the 100.0 ml volumetric flask is 0.0592 M

Explanation:

In the first dilution, Cu2 was diluted ten times (25 / 250 = 1/10). Then, this dilution was diluted again, but now five times (20 / 100 = 1/5). In total, the solution was diluted 50 times (1/10 * 1/5 = 1/50). The final concentration will be 2.96 M / 50 = 0.0592 M

The quantity of the solute or the substance present in the solution is called the concentration. The concentration of the [tex]\rm Cu_{2}[/tex] in the volumetric flask is 0.0592 M.

What is concentration?

Concentration is the molarity of the substance and is given as the ratio of the moles of the solute with the volume in litres.

Given,

  • The volume of [tex]\rm Cu_{2}[/tex] by first pipet = 25 ml
  • Volume of stock solution = 250 ml

The [tex]\rm Cu_{2}[/tex] is diluted ten times at first,

[tex]\dfrac {25}{250}= \dfrac{1}{10}[/tex]

Given,

  • Volume of [tex]\rm Cu_{2}[/tex] by second pipet = 20 ml
  • Volume of stock solution = 100 ml

The [tex]\rm Cu_{2}[/tex] is diluted five times the second time,

[tex]\dfrac {20}{100}= \dfrac{1}{5}[/tex]

Total dilution of the solution was done 50 times as,

[tex]\dfrac{1}{10}\times \dfrac{1}{5} = \dfrac{1}{50}[/tex]

The final concentration of the solution will be,

[tex]\dfrac{2.96 \;\rm M}{50} = 0.0592 \;\rm M[/tex]

Therefore, the final concentration is 0.0592 M.

Learn more about concentration here:

https://brainly.com/question/17325481

Otras preguntas