1. Physical Science WarmUp
I have an object that is 5cm long by 6 cm wide by 2 cm tall. What is the density of this object if it has a mass of 30g?
Will the object above sink or float in water? (Density of water is 1 g/cm³)
***ALL make-up work and/or missing assignments need to be completed by October 25th. This includes all missing tests and quizzes! No work will be accepted after this date.

2. Classifying Matter: Elements, Compounds, and Mixtures
Physical & Chemical Properties and Changes

3. Atoms Elements Compounds Molecules
Pure Substances
A sample of matter that has definite chemical and physical properties.
Atoms
Elements
Compounds
Molecules

4. Elements
pure substance that cannot be separated into simpler substance by physical or chemical means.

5. Compounds
Pure substance composed of two or more different elements joined by chemical bonds.
Made of elements in a specific ratio
that is always the same
Has a chemical formula
Can only be separated by
chemical means, not physically
H2O
NaCl
CO2

6. Mixtures
A combination of two or more pure substances that are not chemically combined.
substances held together by physical forces, not chemical
No chemical change takes place
Each item retains its properties
in the mixture
They can be separated physically
Chem4kids.com

7. 2 types of Mixtures Homogeneous Heterogeneous
Looks the same throughout
Ex) milk, salt water
Heterogeneous
Can see separate layers or components
Ex) Salsa, Salad

8. Properties of Matter
2 types
Physical Properties
Chemical Properties

9. Physical Properties & Changes
Definition
- a characteristic of a substance that can be observed or measured without changing the composition of the substance
ex. viscosity, conductivity, malleability
melting point, boiling point
- remain the same for all pure substances
ALL PHASE CHANGES ARE PHYSICAL!
(Melting, Freezing, Boiling, Condensation, Sublimation, Evaporation, Deposition)

10. Chemical Properties & Changes
Definition
- any ability to produce a change in the composition of matter
- can only be observed when the substances in a sample of matter are changing into a different substance
Ex) Flammability, Reactivity

11. 5 Clues of a Chemical Change
Evidence of a chemical change
- the production of a gas (bubbles)
- the formation of a precipitate
- the presence or absence of heat (hot or cold)
- the emission of light
- a color change during the reaction

12. Warm-Up (10/18)
1. What is the difference between an element, a compound, and a mixture?
2. What is the difference between a homogeneous mixture and a heterogeneous mixture?
3. What is the difference between a physical and a chemical change?
***Test on Density and sigfigs next time you have this class!!!

13. Liquids
Crash Course Chemistry

14. Assignment
1. Finish physical and chemical changes worksheet from last class.
2. Complete the two worksheets at the front of the room. You may write on BOTH of these
***Keep all electronics away. Automatic referral if you do not.