RIGHT SIDE
I.
II.
III.
IV.
Concentration: the amount of solute in a solution
The parts
a. Solute: what gets dissolved (the solid, or the smaller amount of liquid)
b. Solvent: what does the dissolving (almost always water)
c. Solution: solute + solvent
How much solute?
a. A lot = concentrated
b. Not very much = dilute
c. Example: How do you like your chocolate milk?
Grams per Liter (g/L)
a. Concentration = grams of solute/ Liters of solution
b. Example 1: What concentration in g/L is there when you add 15g NaCl
to water to have a total of 1050 mL of solution.
1L = 1000 mL
Solute: NaCl – 15g
Solvent: water
Solution: 1050 mL = 1.05L
Concentration: ?
15g NaCl______
1.05L solution
=14.3 g/L
On your own: example 2
V.
Percent by Volume (V/V) * 100
a. % concentration = volume solute/ volume solution * 100
b. Example 1: If you add 150 mL of water to 50mL of pure rubbing
alcohol, what percent by volume of rubbing alcohol have you made?
Solute: rubbing alcohol -- 50mL
Solvent: water -- 150mL
Solution: 50mL + 150mL = 200mL
% Concentration:?
%C = 50mL * 100
200mL
= 25%
On your own: example 2
LEFT SIDE
Grams per Liter
Example 2: A solution of salt water has a concentration of 5g/L. How many grams
of salt are in a 3L sample of solution?
Solute: salt ?
Solvent: water
Solution: 3L
Concentration: 5 g/L
5g/L =
X_______
3L solution
X = 3*5 = 15g salt
Percent by Volume
Example 2: How much hydrogen peroxide is there in 200mL of 3% hydrogen
peroxide?
Solute: hydrogen peroxide ?
Solvent: [unknown, probably water]
Solution: 200mL
% C: 3%
3% =
X__________ * 100
200mL solution
3 (200) (÷ 100) = 6 mL hydrogen peroxide