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INTRODUCTION TO CONCENTRATION Practice Problems
You must know the differences among the following terms to be successful
making solutions.
Solution: A solution is a homogeneous mixture in which one or more
substances (the solute(s) are dissolved in another substance (the
solvent)).
Concentration: the amount of a solute in a particular volume or mass
of the solution.
Amount: how much of a component is present
Problem 1:
Which of the following are concentrations?
a. 5 g/L
b. 17 grams
c. 84 moles/L
d. 22.2 ng/mL
e. 4 g
f. 0.005 units/L
g. 14 mmoles
Problem 2:
Describe how to prepare 100 mL of 3 grams / mL KCl (The procedure to
prepare this solution is very straightforward and requires no real knowledge
of chemistry! You may solve this problem using either proportions or unit
cancellation.)
Problem 3:
Which of the following solutions is the most concentrated?
30 mg/L
30 g/L
Problem 4:
How much solute is present in 225 mL of a 50 mg/mL solution of NaCl?