**Known Unknown**

Mass of Solute Solution Concentration

Molar Mass of Solute

Volume of Solution

Use molar mass to calculate the number of moles in your solute.

(7.54g FeCl2) 1mol FeCl2 / 126.753g FeCl2

7.54 X 0.00788936

0.0594 mol FeCl2

Use the conversion factor (1L / 1,000 ml) to convert the volume of H2O from ml to L.

(85 ml Solution)(1L / 1,000 ml)

85 X 0.001

0.085 Liters Solution

Substitute known values into the equation for molarity and solve.

Molarity = Moles of Solute / Liters of Solution

Molarity = 0.0954 mol FeCl2 / 0.085 L Solution

0.698 mol FeCl2 / 1 L Solution

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