1. Molarity
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2. Molarity provides a way to measure the concentration of a solution
Molarity (M) = moles of solute
Liters of Solution
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3. Step 1 - Calculate the molar mass of NaOH Na = 23.0 H = 1.0 O = 16.0
Sample Problem: Determine the molarity of a solution made by dissolving 20.0 g of NaOH in sufficient water to yield a 482 mL solution.
Step 1 - Calculate the molar mass of NaOH
Na =
H = 1.0
O = 16.0
1 mol NaOH = g g g = 40.0 g
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4. Step 2 - Calculate the number of moles of solute
20.0 g x 1 mol = mol
40.0 g
Step Convert the volume of solvent into Liters
1 liter is 1000 mL, so the volume of
solution is:
482 mL x 1 liter = liter
1000 mL
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5. Step 4 - Plug these values into your equation
M = mol = mol/liter
0.482 liter
Answer = 1.04 M
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