The concentration of a solution
is a measure of the amount of solute in a specific quantity of solvent. Chemists
express solution concentrations as molarity (abbreviation
M). Molarity is defined as
Let's prepare a 500.0 mL of a 0.0540 M of NaOH.
Calculate how much NaOH is required:
Step 1: Convert 500.0
mL to liter. (show
work) Step 2: Convert liters to moles using molarity
as the conversion factor. (show
work) Step 3: Convert moles of NaOH to mass of NaOH
(in grams) using molar mass as the conversion factor. (show
From the above three steps, we need to weigh out
1.08 grams of NaOH.
Directions for preparing the solution:
1: Weigh out 1.08 grams of NaOH
(Note: this is not the color of NaOH.)
Step 2: Transfer the solid
to a 250 mL beaker that is partly filled with distilled water. Dissolve
the solid in the beaker.
Step 3: Quantitatively transfer
the solution in the beaker to the volumetric flask. Fill the flask with
distilled water up to the mark. Stopper the volumetric flask and shake vigorously
to ensure the solution is well mixed.