1. Chapter 2 Matter

2. Matter: Anything that has mass and takes up space
Atom: is the basic unit of matter
Mass: is the amount of material an object has (do not confuse with weight)
Chemistry: is the study of matter and how it changes
Element: is a substance that cannot be separated into other kinds of substances (lead into gold)

7. Physical Property: is a characteristic of a substance that can be observed without changing the substance into a different substance (ice/liquid water/steam)
Compound: is a substance made up of atoms of different elements
Molecule: is the smallest particle of a substance that has the all the properties of the substance
Chemical Property: is a characteristic that describes how a substance changes into a different substance (elements combine with each other in chemical reactions)
Chemical bonds: store energy

8. Compounds

9. Chemical Formula Represents compounds Example:
Molecule of indigo Dye for blue jeans
C16H10N2O2
Three molecules of table sugar
3C12H22O11

10. Pure Substance
A sample of matter, either a single element (O) or a single compound (H2O), that has definite chemical and physical properties
Elements: Na or Cl
Compound: NaCl
Elements and compounds are pure substances, but mixtures are not.

11. Mixtures Classified by how well the substances mix
Heterogeneous: mixture that is NOT evenly distributed
Salad
Homogeneous: mixture that is evenly distributed
Vinegar and water
Gasoline (hundreds of liquids that are miscible)
Carbonated beverage

13. Mixture

14. Properties of Matter
Physical: characteristics that can be observed without changing the identity of the substance
Density
Melting point (solid to a liquid)
Boiling point (liquid to a gas)
Reactivity (chemical property)
Can be separated by physical means

17. Density Ratio of the mass of a substance to its volume
D = mass/volume = m / v

22. Chemical Property
Reactivity: the capacity of a substance to combine chemically with another substance
Describes how a substance changes into a new substance, either by combining with other elements or by breaking apart into new substances
Flammability (ability to burn)
Iron and oxygen yielding rust
Na and Cl yielding salt (NaCl)
Some are reversible
Example of carbonic acid in soda

25. Changes of Matter
Physical change affects one or more physical properties of a substance without changing the identity of the substance
Melting of ice (solid to liquid)
Crushing of a can
Dissolving of sugar in water
Dissolving of CO2 in water
Dissolving of air in ice cream (soft ice cream)

30. Changes of Matter
Chemical change happens when one or more substances are changed into entirely new substances that have different properties (new substance has formed).
Digesting of food
Burn with oxygen
Na and Cl to form NaCl
Iron rusting
Copper turning green