1. Topic: Classifying Matter
Which of the following is a physical change that requires energy?
H2O (l)  H2(g) + O2 (g)
H2O (l)  H2O (s)
H2O (s)  H2O (l)
H2(g) + O2 (g)  H2O (l)

2. Matter Substances Mixtures Mixtures  Separated by physical methods
Elements
Compounds
Heterogeneous
Homogeneous
Can it be separated by physical methods NO
YES
Mixtures  Separated by physical methods
Compounds  Separated by chemical methods

3. Pure Substance Homogenous (uniform throughout) Definite composition
Same characteristic properties regardless of source which are pure substances

4. Element Substance that: Formulas have 1 uppercase letter
cannot be broken down or decomposed into simpler substance
only 1 kind of atom
has definite properties
Formulas have 1 uppercase letter Cu Cu Cu Cu F2 F F F F

5. Atom
smallest particle of element that retains properties of element & can undergo a chemical rxn
Atoms can be combined to form molecules =2 or more total atoms F F F F

6.         Particle Diagrams Atoms of a monatomic (1) element       
Molecules of a diatomic (2) element        

7. These seven elements are always diatomicF F2
Cl2 Cl
Br2 Br I2 I

8. Element Song
Big Bang Version sung by Sheldon

9. Compounds 2 or more elements chemically combined in a definite ratio
Properties are different from those of elements formed from
Only Broken into elements by chemical decomposition reaction
Formulas have 2 or more uppercase letters
HCl Cl H H Cl Cl H
H2O O H H O H H

10. 2Na + Cl2  2NaCl Na = atom, element Cl2 = molecule, element
NaCl = molecule, compound
Atoms or Molecules?
Element or Compound?

11.          Particle Diagrams
Molecules of a triatomic (3) compound         
Mixture:
monatomic element, diatomic element, triatomic compound             

12. Made of Ions
Na+1Cl-1 = NaCl

13. Mixtures
Combo of 2 or more pure substances (elements + elements) (elements + compounds) (compounds + compounds)
Physically combined not chemically combined
Each substance retains its own identity and properties

14. Mixtures Variable composition No unique properties
(Think of sugar and salt mixed together)
Separated by physical methods
May be homogeneous or heterogeneous

15. Types of Mixtures
Heterogeneous: definite variation in composition, individual components visible - scatters light (can’t shine light through)
Oil in water
Salad dressing
Granite

16. Colloids (type of heterogeneous mix.)
Particles are suspended- they are too small to see
Aerosols: solid or liquid particles in gas
Ex: Smoke/Fog: solid in a gas
Gas in liquid:
Ex: whipped cream
Emulsion: liquid in liquid
Ex: mayonnaise (oil suspended in water – use egg yolk to
Sols: solid particles in a liquid
Ex: Milk of Magnesia (solid magnesium hydroxide in water)
Gels: Liquid in solid
Ex: Quicksand: sand in water

17. Suspensions (type of heterogeneous mix.)
Particles are larger
can be evenly distributed by mechanical means (shaking the contents)
Settle out on standing

18. Solutions in gas & liquid phases transmit light
Homogeneous (aka solutions): constant composition throughout, individual components not visible
Solutions in gas & liquid phases
transmit light
particles not big enough to scatter light
look translucent

19. RECAP: Solution vs Suspension
Solutions in gas & liquid phases
transmit light
particles not big enough to scatter light
look translucent
Suspensions look cloudy
particles big enough to scatter light
settle on standing

20. Solution(homogenous) vs Suspension(heterogeneous)

21. Solution(homogenous) vs Suspension(heterogeneous)
CuSO4(aq)
Solution(homogenous) vs Suspension(heterogeneous)

22. Heterogeneous Mixture: elements & elements O2 in the gas phase Or
Homogeneous?
Compounds?
Elements?
Solid?
Liquid?
Gas?
Homogenous Mixture:
Compounds & elements
Both in liquid phase O H H O H H O H H O H O F- H H F- O F- H H F- O H F- O F- O H F- H H H H F- O O O
Heterogeneous Mixture:
elements & elements
O2 in the gas phase
K in the solid phase O O O K K K K K K O O