Mixtures

Question 1

Define a pure substance:

Answer 1

Is matter that has a fixed composition and unique properties.
- Contains only 1 type of element or compound.
- Homogenous

Question 2

Define a mixture:

Answer 2

Contains at least two physically combined compounds.
- Can be homo/heterogenous

Question 3

Homogenous substances:

Answer 3

The composition of the substance is same throughout.
1) Element: one type of atom.
2) Compound: 2 or more chemically combined elements (CO2, H2O)
3) Solution: special kind of mixture 2 phases - Solute (dissolves), solvent (does the dissolving) (e.x alloys, moist air)

Question 4

Heterogenous mattter:

Answer 4

The composition of the substance is different throughout.
- Always Mixture (solutions are mixtures that are not heterogenous).
- 2 or more physically combined substances (element/substances)

Question 5

What are the three classes of mixtures?

Answer 5

• Solution
• Colloid
• Suspension

Question 6

Describe the tyndall effect?

Answer 6

Scattering of light by particles in a colloid or suspension.

Question 7

Solution (provide e.x.)

Answer 7

Particle type - ions, atoms
Particle size - small
Tyndall effect? - No
Settle while standing - No
Separation by filtration - No
E.x. Salt water, air

Question 8

Colloid (Provide e.x.)

Answer 8

Particle type - small clusters
particle size - medium
Tyndall effect? - Yes
Settle while standing - No
Separation by filtration - No
E.x. Soot, fog, mayonnaise, milk

Question 9

Suspension (Provide e.x.)

Answer 9

Particle type - Large clusters
Particle size - large
Tyndall effect - Yes
Settle while standing - Yes
Separation by filtration - Yes
E.x. Muddy water, Italian dressing

Question 10

Homogenous Mixtures:

Answer 10

Are mixtures in which the components are evenly distributed among each other. Also known as a solution.

Question 11

States of matter in solution:

Answer 11

-Gas in gas
-Gas in liquid
-Gas in solid
-Liquid in liquid
- Liquid in solid
- Solid in liquid
- Solid in solid