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3 years ago

What is the concentration of a solution formed by diluting 25.0 ml of a 3.2 M NaCl solution to 135.0 ml?

Chemistry

2 answers:

Irina-Kira [14]3 years ago

4 0

Answer:

B) 0.59 M NaCl.

Explanation:

It is known that the no. of millimoles of NaCl before dilution = the no. of millimoles of NaCl after dilution.

∵ (MV) before dilution = (MV) after dilution.

∴ M after dilution = (MV) before dilution / V after dilution = (3.2 M)(25.0 mL)/(135.0 mL) = 0.5926 M ≅ 0.59 M.

Tresset [83]3 years ago

4 0

0.59 M

<h3>Further explanation </h3>

Given:

NaCl solution

V₁ = 25.0 ml
M₁ = 3.2 M
V₂ = 135.0 ml

Question:

M₂ = ?

The Process:

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:

$\boxed{ \ M_1V_1 = M_2V_2 \ }$ .

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

$\boxed{ \ M_2 = \frac{M_1V_1}{V_2} \ }$ .

Let us calculate the concentration of a solution formed.

$\boxed{ \ M_2 = \frac{3.2 \times 25.0}{135.0} \ }$ .

Thus the concentration of a NaCl solution formed is 0.59 M.

_ _ _ _ _ _ _ _ _ _

Remember, the amount of water that needs to be added is 135.0 ml - 25.0 ml = 110 ml.

_ _ _ _ _ _ _ _ _ _

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.

$\boxed{ \ molarity = \frac{moles \ of \ solute}{liters \ of \ solution} \ }$

<h3>Learn more </h3>

An example of the dilution of a solution brainly.com/question/4516437
How many moles of HNO₃ are present in the dilute solution? brainly.com/question/13501499
To make a 0.500 M solution, one could take 0.500 moles of solute and add? brainly.com/question/10278982

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