1. COMPOSITION OF MATTER

2. Objectives
Understand that God created all things on Earth using 91 elements
Distinguish between pure substances and mixtures
Distinguish between compounds, elements, and mixtures
State the basic properties that all mixtures share
Distinguish between heterogeneous mixtures and homogeneous mixtures
Separate mixtures using various methods
Distinguish between a colloid and a suspension.
Distinguish between a physical and chemical properties.
Distinguish between a physical and chemical change.

3. Element Pure substance One kind of atom
Represented by 1 or 2 letter symbol (the first letter will always be capitalized, the second lower case)
Examples: Helium ( He ), oxygen ( O2 ), copper (Cu)
Categorized on the periodic table
God created everything with 91 elements. Man has create more since.

4. Compound 2 or more elements are chemically combined
Represented by a chemical formula. The formula shows what elements are in the compound & how many atoms of each element are present.
Examples: sodium chloride (NaCl), water (H2O).
Combine in same proportion
Cannot be separated physically, must be separated by a chemical reaction.

5. Mixture two or more substances physically combined
Do not combined in some proportion
Can be separated by physical means
Heterogeneous mixture – not uniform (examples include: ocean, muddy water, air)
Homogeneous mixture (aka solutions) - uniform (examples include: soda, salt water, brass, bronze)
Alloy : mixture of two or more metals or a metal and a non-metal

7. Difference between a compound and a mixture…..

8. Physical Properties
Physical properties can be observed without chemically changing matter.
This means we do not need to have a chemical reaction to observe it..
Examples: color, shape, smell

9. Chemical Properties
Chemical properties describe how a substance reacts with other substances.
Examples:
Reactivity : how a substance reacts with other substances
Corrotion: metals easily corrode, so we paint them
Combustibility: it will burn – like wood
Flammability: it will ignite easily – gasoline is both flammable and combustible

10. Physical or Chemical? Color Texture Acidity Solubility Ability to rust
Mass
Phase Changes

11. Physical or Chemical? Color - physical Texture - physical
Acidity - chemical
Solubility - physical
Ability to rust - chemical
Mass - physical
Phase Changes – physical
Solubility: how one substance dissolves in another without chemically changing.

12. Physical Changes No change in identity of the substance
At the molecular level, the substance remain the same
Examples: breaking, tearing, phase changes

13. Chemical Changes Chemical Change: one or more substances produced.
One or more substances are converted into one or more different substances.
Examples: rusting, burning, forming salt from sodium and chlorine.

14. Physical or Chemical Change?
Digesting Food
Evaporation
Tarnishing
Breaking glass
Burning wood

15. Physical or Chemical Change?
Digesting Food - chemical
Evaporation - physical
Tarnishing - chemical
Breaking glass - physical
Burning wood - chemical

16. Suspensions and Colloids
Mixture
Particles will settle.
Partlicles are large enough to block light.
Examples: salad dressing, sand water, snow globe.
Colloid:
Particles will not settle.
Scatter light.