Question

An aqueous magnesium chloride solution is made by dissolving 6.92 6.92 moles of MgCl 2 MgCl2 in sufficient water so that the final volume of the solution is 2.00 L 2.00 L . Calculate the molarity of the MgCl 2 MgCl2 solution.

Answer 1

Answer:

[MgCl₂] = 0.036 M

Explanation:

Molarity are the moles of solute in 1L of solution.

For this case, our solution's volume is 2L

First of all, we convert the mass of solute (MgCl₂) to moles

6.92 g . 1mol / 95.2 g = 0.0727 moles

Now, we make a rule of three:

In 2L of solution we have 0.0727 moles of solute

Then, in 1L of solution we may have, 1L . 0.0727 mol / 2L = 0.036 M