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Given the formula m1v1=m2v2, where m indicates concentration and v indicates volume, which equation represents the correct way to find the concentration of the dilute solution (m2)?

Respuesta :

Louli
The formula is m1v1 = m2v2.

If m1, v1 and v2 are given, then the concentration of the dilute solution (m2) can simply be calculated by substituting the givens in the mentioned equation then using cross multiplication to get the unknown value as follow:

m2 = (m1v1) / v2
BladeRunner212

M₂ = (M₁V₁) / V₂

Further explanation

Dilution represents the addition of a solvent (water) without adding solutes. In dilution, the mole of the solute remains, so the concentration of the solution will drop.

When calculating dilution factors, the units of volume and concentration must remain consistent.

Dilution calculations can be typically performed following the formula:

[tex]\boxed{ \ M_1V_1 = M_2V_2 \ }[/tex].

with,

  • V₁ and V₂ as volume before and after dilution
  • M₁ and M₂ as the molarity of the solution before and after dilution.

The equation which represents the correct way to find the concentration of the dilute solution (M₂) is

[tex]\boxed{ \ M_2 = \frac{M_1V_1}{V_2} \ }[/tex].

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Example:

How much must be dissolved to carry out 5 liters of 0.4 M methanol solution? How much water do you require adding?

  • M₁ = 25 M
  • V₂ = 5 L
  • M₂ = 0.4 M
  • V₁ = ?

[tex]\boxed{ \ V_1 = \frac{M_2V_2}{M_1} \ }[/tex]

[tex]\boxed{ \ V_1 = \frac{0.4 \times 5}{25} \ }[/tex]

[tex]\boxed{ \ V_1 = \frac{0.4}{5} \ }[/tex]

[tex]\boxed{ \ V_1 = \frac{0.8}{10} \ }[/tex]

[tex]\boxed{ \ V_1 = \frac{8}{100} \ }[/tex]

  • Thus we have 0.08 L or 80 mL of 25 M methanol solution.
  • The amount of water that needs to be added is 5 L - 0.08 L = 4.92 L or 492 mL.

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Notes:

  • A solution consists precisely of a solute and a solvent.  
  • There are several ways to properly express the concentration of a solution, one of which is molarity. Molarity is also known as molar concentration with the symbol unit M or molar or mole/L.
  • The molarity (M) of a solution is calculated by allowing the moles of solute and divided by the number of liters of solution.

[tex]\boxed{ \ molarity = \frac{moles \ of \ solute}{liters \ of \ solution} \ }[/tex]

Learn more

  1. To make a 0.500 M solution, one could take 0.500 moles of solute and add? https://brainly.com/question/10278982
  2. The molality and mole fraction of water https://brainly.com/question/10861444  
  3. How many liters of the  50%  solution and how many liters of the  90%  solution will be used? https://brainly.com/question/13034221

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