1. Matter: Properties & Changes
Chapter 2 notes

2. (2.1) Physical Properties of Matter
can be observed or measured without changing the composition of the sample
Examples: color, phase, melting or boiling point, density, hardness, odor, taste

3. States of Matter Solid (s) - definite volume and shape
Liquid (l) - definite volume, but not shape
Gas (g) - no definite volume or shape
Plasma - highly ionized gas
(s)
(l)
(g)

4. sToP & tHinK
Which state or states of matter take(s) the shape of its container?
Which state or states of matter can change in volume (without adding or subtracting from the sample)?

5. Physical Changes
Physical changes alter a substance without changing its composition

6. sToP & tHinK Which of the following are physical properties?
liquid at room temperature
reacts with metals to form H2 gas
acids and bases combine to form water and a ‘salt’
boils at 145 degrees Celsius

7. (2.2) Mixtures…
Mixture - a combination of two or more pure substances, in which each substance retains its individual chemical properties
Heterogeneous mixture - does not blend smoothly, individual substances are distinct
Homogeneous mixture - solution; has a constant composition throughout

8. sToP & tHinK
Heterogenous or Homogeneous?
(1)
(2)

9. Separating Mixtures
Filtration - porous barrier separates solid from liquid
Distillation - liquids separated by differences in boiling point
Crystallization - forms pure solids from dissolved substances
Chromatography - separation based on ability to travel or be drawn across a material

10. filtration

11. distillation

12. crystallization

13. chromatography

14. sToP & tHinK
What separation technique is shown in the following pictures? B A

15. (2.3) Elements & Compounds
Elements - pure substances that cannot be broken down into simpler substances
on the Periodic Table!
Compounds - two or more elements bonded together that can be broken down

16. sToP & tHinK
In your own words, what is the difference between an element and a compound?
Classify the following as being elements or compounds
Sodium
Sodium chloride
Oxygen
Carbon dioxide
Copper

17. (2.4) Chemical Properties
the ability of a substance to undergo chemical change
Examples: “reacts with oxygen to form rust”, “forms a deep blue solution when in contact with ammonia”

18. Chemical Changes
Chemical changes alter the composition so that a new substance forms
Evidence of chemical change: formation of a gas or solid (precipitate), smoke, fire, an odor, temperature change, color change
Law of Conservation of Mass: composition changes, but mass doesn’t

19. sToP & tHinK
Substance A is a yellow liquid and substance B is a blue liquid. The two are mixed and form a green liquid and a white solid.
What evidence suggests a chemical change occurred?
What other things could you look for to determine if there was a chemical change?

20. sToP & tHinK - which shows physical change and which shows chemical change?
link to change animation #1
link to change animation #2