Molarity and Dilution H

Front

What is Molarity?

Back

Molarity (M) is a measure of concentration defined as the number of moles of solute per liter of solution.

Front

How do you calculate Molarity?

Back

Molarity = moles of solute / liters of solution.

Front

What is the formula to find moles from Molarity and volume?

Back

Moles = Molarity × Volume (in liters).

Front

If you have 40.0 g of NaCl, how do you find the moles of NaCl?

Back

Moles = mass (g) / molar mass (g/mol). For NaCl, molar mass = 58.44 g/mol.

Front

What is the molarity of a solution with 0.50 moles of NaCl in 400.0 mL of solution?

Back

Molarity = 0.50 moles / 0.4 L = 1.25 M.

Front

What is the volume of a 0.20 M solution containing 0.30 moles of Na2SO4?

Back

Volume = moles / Molarity = 0.30 moles / 0.20 M = 1.5 L.

Front

How many moles are in 2.5 L of a 3.8 M solution?

Back

Moles = Molarity × Volume = 3.8 M × 2.5 L = 9.5 moles.

Front

What happens to the concentration when you dilute a solution?

Back

The concentration decreases when you add more solvent.

Front

What is the process of dilution?

Back

Dilution is the process of adding more solvent to a solution to decrease its concentration.

Front

If you have a 2.0 M solution and dilute it to 1.0 L, what happens to the moles of solute?

Back

The moles of solute remain the same; only the concentration changes.