1. Classifying Matter
Chapter 15

2. Introduction
Apple Tree, Air, Octopus, Sweater, Computer, Cookie, and Light Bulb…
What do these objects share in common?
All of them are made of matter!!!
Every material that you can hold or touch is made of matter.

4. What is Chemistry?
Chemistry is the study of matter and how it changes.
This year we will explore the makeup, properties, changes, and interactions of matter.
Chemists classify matter into 3 categories: elements, compounds, and mixtures.

5. Elements
An element is a substance that cannot be broken down into another substance.
The smallest unit of an element is an atom.
Each element is made of only ONE kind of atom.
Elements are represented by one or two letter symbols that are understood world wide (found on the Periodic Table).

7. Molecule vs Compound
= all compounds are molecules, but not all molecules are compounds
A molecule is formed when two or more of THE SAME atom join together.
Example: N2, O3

8. Molecule vs Compound
= all compounds are molecules, but not all molecules are compounds
A compound is formed when two or more DIFFERENT atoms join together.
Example: CH4, CO2

9. Is water an atom, a molecule, or a compound?
H2O

10. C12H22O11 Compounds Compounds are written using a Chemical Formula.
A Chemical Formula uses the element abbreviation and subscripts that shows the atoms in a compound.
Table Sugar…
C12H22O11

11. C8H10N4O2

12. C16H10N2O2 Chemical Formula 16 Carbon Atoms 2 Oxygen Atoms
10 Hydrogen Atoms
2 Nitrogen Atoms
This is the chemical formula for the molecule indigo. It has four elements and 30 atoms.

13. Pure Substance
Are matter with a fixed composition and definite properties
Only elements and compounds are pure substances

14. Mixtures A mixture IS NOT a pure substance.
Two or more pure substances blended together make mixtures
Are made of more than one pure substance, such as water, sugars, acids, and vitamins
For example, grape juice

15. Mixtures
They are classified by how well the substances are mixed in them.
Heterogeneous Mixtures – are not evenly distributed and things can easily be removed from the mixture. (ex: Chicken Salad).
Homogenous Mixtures – are mixed evenly (ex: Vinegar).

16. Heterogenous

17. Homogenous

19. Solutions and Other Mixtures
Solution – A homogeneous mixture of two or more pure substances uniformly spread throughout a single phase (remember that a homogeneous mixture is a uniform blend of two or more pure substances)
Solute – the substance that dissolves in a solution
Solvent – the substance that dissolves the solute to make a solution

22. Mixtures Miscible Immiscible
Describes two or more liquids that are able to dissolve into each other in various proportions
Immiscible
Describes two or more liquids that do not mix into each other

24. Summary Matter has mass and occupies space.
An element is a pure substance that cannot be broken down into a simpler substance.
An atom is the smallest particle of matter that has the properties of a particular element.
Atoms can join together to make molecules.

25. Summary
A pure substance that contains two or more elements is a compound.
A pure substance can be represented by a chemical formula.
A homogenous mixture is uniform throughout.
A heterogeneous mixture is one where the individual substances are not uniform throughout.