Different Ways of Expressing
Concentration
Grade 10 ST
Concentration

A solution is composed of a solute
dissolved in a solvent
Solute: substance being dissolved
Solvent: substance doing the dissolving
Concentration: the amount of solute in a
given quantity of solvent
Ways of Expressing Concentration
In g/L
 6 g/L means “6g of solute dissolved in 1 L
of solution”
 To find the concentration, we can use the
formula
Formula: C= m
V
C= concentration (g/L)
m= mass of solute (g)
V= Volume of solvent (L)
Ways of Expressing Concentration
As % (m/V)
12 % (m/V) means “ 12 g of solute dissolved
in 100 mL of solution”
To solve problems, set – up a ratio and
cross multiply
% (m/V) Example
40 g of Kool –Aid are dissolved in 1.2 L of
solution. What is the concentration of
this solution expressed as a % (m/V)
% (m/V) Example
A 600 mL volumetric flask is filled with a
solution of concentration 5% (m/V). What
is the mass of the solute contained in this
bottle?
Ways of Expressing Concentration
As % (m/m)
8 % (m/m) means “ 8 g of solute dissolved
in 100g of solution”
To solve problems, set up a ratio and cross
multiply
% (m/m) Example
30 g of Kool- Aid are dissolved in 500 mL of
water. What is the concentration of this
solution expressed as % (m/m)
% (m/m) Example
A solution was made using 8g of solute and
it has a concentration of 6% (m/m). What
is the mass of the solution?
Ways of Expressing Concentration
As % (V/V)
10% (V/V) means “10 mL of solute
dissolved in 100mL of solution”
To solve problems, set up a ratio and cross
multiply
% (V/V) Example
A 750 mL bottle of wine contains 90 mL of
alcohol. What is the alcohol concentration
of this wine? ( in %(V/V))
% (V/V) Example
Vinegar is really just 5% (V/V) acetic acid.
What volume of acetic acid is contained
in a 600 mL bottle of vinegar
Ways of Expressing Concentration
In ppm (parts per million)
125 ppm means “125 g of solute in 1 000
000g of solution”
 We use ppm to express very small
concentrations.
 To solve problems, set up a ratio and
cross multiply
ppm Example
A certain brand of bottled water contains
25 ppm of chlorine ions. How many grams
of chlorine ions are present in a bottle
that contains 500 mL?
ppm Example
What is the concentration (in ppm) of a
200g sample of soil that contains 0.01g of
lead?