Molarity & Dilutions

Front

What is molarity?

Back

Molarity is a measure of the concentration of a solute in a solution, expressed as moles of solute per liter of solution (mol/L).

Front

How do you calculate molarity?

Back

Molarity (M) = moles of solute / liters of solution.

Front

What is the formula to find the number of moles from molarity and volume?

Back

Number of moles = Molarity (M) × Volume (L).

Front

If you have a 3.8 M solution, how many moles are in 2.5 L?

Back

9.5 mol (calculated as 3.8 M × 2.5 L).

Front

What is the molarity of a solution containing 4.00 grams of KNO3 in 3.80 L?

Back

0.0104 M (calculated using the molar mass of KNO3).

Front

What does a concentrated solution mean?

Back

A concentrated solution has a high amount of solute relative to the amount of solvent.

Front

What does a diluted solution mean?

Back

A diluted solution has a low amount of solute relative to the amount of solvent.

Front

How many moles of NaCl are in a solution with a molarity of 8.59 M and a volume of 125 mL?

Back

1.07 mol (calculated as 8.59 M × 0.125 L).

Front

What is the relationship between moles, molarity, and volume?

Back

Moles = Molarity × Volume; this relationship helps in calculating any one of the three if the other two are known.

Front

What is the unit of molarity?

Back

The unit of molarity is moles per liter (mol/L).