1. Warm-Up: 2/4 Classifying Elements
Head a sheet of paper and title it: Elements, Compounds, and Mixtures Notes
Science Binder page 32
Make a subheading (smaller title under the main title) – Warm-Up: 2/3 Classifying Elements
Write a short paragraph explaining what makes something an element. Include examples.

2. Elements, Compounds and Mixtures Notes
Science Binder p. 32

3. Classification of Substances
Elements
Molecules
Compounds
Mixtures

4. Elements Elements are substances made up of only one type of atom.
Example  Hydrogen, Gold.

5. Elements
Pure substance that cannot be separated into simpler substances by physical or chemical means.
Pure substance- a substance in which there is only one type of particle (atom or molecule)

7. Periodic Table of Elements

8. Molecule A molecule is made up of two or more atoms chemically bonded.
Atoms can be the same or different!

9. Compounds
Compounds are pure substances made up of two or more different types of atoms chemically bonded.

10. Properties of Compounds
When a compound is formed during a chemical reaction its properties differ from those of the elements it is made of.
Example: Water is made from hydrogen and oxygen.
Hydrogen  flammable gas
Oxygen  colorless gas.

11. Compounds
Represented by chemical formulas with two or more chemical symbols (each capital letter = a new chemical symbol/element)
NaCl = sodium chloride (table salt)
H2O2 = hydrogen peroxide
C6H12O6 = glucose (sugar plants make from photosynthesis)

12. Chemical Formulas
subscript- small number located at the bottom right of a chemical symbol, and gives the number of atoms for the element in that molecule

13. Mixtures
A mixture consists of two or more different substances mingled together but not chemically combined.
Examples: Sea – water and salt
Air – nitrogen, oxygen …
Soil – sand, clay, humus …

14. Compare mixtures and Compounds.

15. Mixture
Compound
The amounts of the substances in the mixture can vary.
The elements in a compound are always present in the same fixed proportion.
A mixture contains two or more substances
A compound is a single substance.
The properties of a mixture are similar to those of the substances in a mixture.
The properties of a compound are different to those of the elements which reacted to form it.
There are practically no energy changes when a mixture is made
Heat is usually given out or taken in when a compound is formed.
It is usually easy to separate the components of a mixture.
It is usually difficult to separate the components of a compound.

16. iron particles Key: one iron particle
strong bonds between iron particles
iron particles held together by strong bonds

17. iron particles iron particles are attracted to a magnet
iron particles diagram

18. sulfur particles Key: one sulfur particle
strong bonds between sulfur particles
sulfur particles held together by strong bonds

19. sulfur particles sulfur particles are not attracted to a magnet
sulfur particles diagram

20. iron particles
sulfur particles

21. A mixture of iron and sulfur particles
What’s this?
A mixture of iron and sulfur particles
strong bonds between iron particles
strong bonds between sulfur particles

22. A mixture of iron and sulfur particles
A magnet attracts the iron particles
but not the sulfur particles.
The mixture is separated
mixture diagram

23. A compound between iron and sulfur particles
What’s this?
A compound between iron and sulfur particles
one iron particle
one sulfur particle
strong bonds between iron and sulfur particles

24. A compound between iron and sulfur particles
strong bonds between iron and sulfur particles
The magnet cannot separate iron and sulfur particles in a compound
compound diagram

25. A

26. B

27. C

28. D

29. E

30. F

31. G

32. H