This document defines solutions and describes different types of solutions, concentration, and colloids. It discusses gaseous, liquid, and solid solutions. Ways to express concentration include percentage by mass or volume, molarity, molality, and mole fraction. Colloids are heterogeneous mixtures where one substance is dispersed as very fine particles in another substance. Colloids exhibit the Tyndall effect and can have solid, liquid, or gas phases dispersed in solid, liquid, or gas media.

2. SOLUTIONS

3. DEFINITION
• a mixture where the components
are uniformly intermingled
• a mixture that is homogeneous

4. TYPES
• Gaseous solution
• Liquid solution
• Solid solution

5. Recall
Solute
• what is dissolved in a solution
Mass
• a measure of the amount of matter in
an object (g or kg)
Volume
• measures the size of an object using length
measurements in three dimensions (ml or L)

6. Recall
Mole (mol)
• also known as Avogadro's Number
• number that is used in making calculations
involving atoms and molecules
• 1 mol is equal to 6.022 x 1023 atoms or molecules
• Molar Mass (MM) of elements and compounds is
the mass, in grams, equal to the atomic and
formula masses of those elements and
compounds. The unit of Molar Mass
is grams/mole

7. Practice
Calculate the molar mass of the following:
• CO2 = 44.01 grams/mole
• H2O = 18.02 grams/mole
• NaCl = 58.44 grams/mole

8. CONCENTRATION
Relative Amounts
of Solute and Solvent
in a Solution

9. Ways to Express the Relative Amounts
of Solute and Solvent in a Solution
• Percent concentration (by mass; by volume)
• Molarity (M)
• Molality (m)
• Mole fraction (X)

10. ● Percent Composition
(by mass; by volume)
We need two pieces of information to calculate
the percent by mass of a solute in a solution:
• mass/volume of the solute in the solution
• mass/volume of the solution

11. By mass:
• % (w/w) =
By volume:
• % (v/v) =
100x
solutionmass
solutemass
100x
solutionvolume
solutevolume
● Percent Composition
(by mass; by volume)

12. Practice
• 10 g salt and 70 g water are mixed to make a
solution. Find the concentration of the
solution by percent mass.
12.5 %

13. Practice
• The concentration by volume of a 1.5 L NaCl
solution is 40 %. Find the amount of solute in
this solution.
0.6 L

14. ● Molarity (M)
Molarity tells us the number of moles of solute
in exactly one liter of a solution.
We need two pieces of information to calculate
the molarity of a solute in a solution:
• moles of solute present in the solutio
• volume of solution (in liters) containing the
solute

15. ● Molarity (M)

16. Practice
• What is the molarity of a solution that
contains 1.724 moles of H2SO4 in 2.50 L of
solution?
0.690 M H2SO4

17. Practice
• What is the molarity of a solution prepared by
dissolving 25.0 g of HCl (g) in enough water to
make 150.0 mL of solution?
4.57 M HCl

18. ● Molality (m)
Molality, m, tells us the number of moles of
solute dissolved in exactly one kilogram of
solvent.
We need two pieces of information to calculate
the molality of a solute in a solution:
• moles of solute present in the solution
• mass of solvent (in kilograms) in the solution

19. ● Molality (m)
Recall: density of water = 1.00 g / mL or 1 kg/L

20. Practice
• Suppose you had 58.44 grams of NaCl and you
dissolved it in exactly 2.00 kg of pure water.
What would be the molality of the solution?
0.5 m

21. Practice
• 80.0 grams of glucose (C6H12O6, mol. wt = 180
g/mol) is dissolved in 1.00 L of water. What is
its molality?
0.44 m

22. ● Mole Fraction (X)
The mole fraction, X, of a component in a
solution is the ratio of the number of moles
of that component to the total number of
moles of all components in the solution.
To calculate mole fraction, we need to know:
• number of moles of each component present
in the solution

23. ● Mole Fraction (X)
NOTE:
The sum of the mole fractions
for each component in a solution will be equal to

24. Practice
• A solution is prepared by mixing 25.0 g of
water, H2O, and 25.0 g of ethanol, C2H5OH.
Determine the mole fractions of each
substance.
XH2O = 0.71
XC2H5OH = 0.29

25. COLLOIDS

26. • a heterogeneous system in which
one substance is dispersed
(dispersed phase) as very fine
particles in another substance called
dispersion medium
DEFINITION

27. • the size of the dispersed molecule is
larger than a simple molecule
(having diameter between 1 to 1000
nm) but small enough to remain
suspended

28. • an intermediate state between
suspensions and solutions

29. THE TYNDALL EFFECT
• colloidal suspensions exhibit light scattering
• named after its discoverer, the 19th-century
British physicist John Tyndall
• a special instance of diffraction (bending of
light)
• often used as a measure of the existence of a
colloid
• visible in colloids as weak as 0.1 ppm
(exception?)

30. TYPES AND EXAMPLES
based on physical state of dispersion
medium and dispersed phase

31. medium: SOLID
phase: SOLID
Gemstones
Pearls
Some coloured glass

32. medium: SOLID
phase: GAS
Pumice Foam Rubber

33. medium: SOLID
phase: LIQUID
Cheese Shoe polish Butter
Jellies Jam

34. medium: LIQUID
phase: LIQUID
Milk Hair Cream
Cod liver oil

35. medium: LIQUID
phase: GAS
Froth
Soap lather
Whipped cream

36. medium: LIQUID
phase: SOLID
Paints
Gum
Muddy water

37. medium: GAS
phase: LIQUID
Fog
Clouds
Insecticide spray

38. medium: GAD
phase: SOLID
Smoke Dust

39. medium: GAS
phase: GAS

40. At a glance
MEDIUM PHASE SOLID LIQUID GAS
SOLID Solis Sols
gemstones, pearls,
some coloured glass
Gels
cheese, butter,
shoe polish, jellies, jam
Solid Sols
pumice, foam rubber
LIQUID Sols
gum, paint, muddy water
Emulsion
milk, hair cream,
cod liver oil
Foam
froth, whipped cream,
soap lather
GAS Aerosol
smoke, dust
Aerosol
clouds, spray, fog
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42. e o s