To make clearer
the concentration of a solution, chemists calculate molarity (M).
Molarity is the number of moles of solute
per liter of solution.
For
example: Calculate the molarity of a solution where 38.0 grams
of sodium chloride is dissolved in water to make 900. mL of solution.
You
must first convert grams to moles by dividing the compound's molar mass.
(38.0 grams) / (58.5 grams/mole) = 0.650 moles
Next convert mL of solution to liters of solution.
900. / 1000. = 0.900 liters
Now, plug it in the formula and solve.
Molarity = 0.650 moles / 0.900 liter= 0.722 Molar
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