1. 1.2 Matter and Its Properties
Ch. 1: Matter and Change
1.2 Matter and Its Properties

2. Terms Matter- anything that has mass and volume
Atom- smallest unit of an element that keeps the properties of element
Element- pure substance made of only one type of atom
Compound- substance made of 2 or more types of atoms that are chemically bonded
Molecule- type of compound in which bonds are covalent bonds

3. Properties of Matter
chemists use characteristic properties to tell substances apart and to separate them
some properties define a group of substances

4. Types of Properties Extensive- depend on the amount of matter
Ex: volume, mass, amount of energy
Intensive- do not depend on the amount
Ex: density, boiling point, ability to conduct

5. Types of Properties
Physical- characteristics that can be observed or measured without changing the identity of a substance
Chemical- relates to a substances ability to undergo changes that transform it into a different substance
Easiest to see when a chemical is reacting

6. Physical Changes in Matter
Includes all changes of state (physical changes of a substance from one state to another)
change in a substance that doesn’t change the identity of the substance
Ex. grinding, cutting, melting, boiling

7. Solid definite volume definite shape
atoms are packed together in fixed positions
strong attractive forces between atoms
only vibrate in place

8. Liquid definite volume indefinite shape atoms are close together
atoms can overcome attractive forces to flow

9. Gases indefinite volume indefinite shape atoms move very quickly
atoms are far apart
pretty weak attractive forces

10. Changes of State

11. Plasma high temperature state in which atoms lose their electrons
Ex. the sun

12. Chemical Changes in Matter
a change in which a substance is converted into a different substance
same as chemical reaction
doesn’t change the amount of matter present
reactants- substances that react
products- substances that form

13. mercury + iodine  mercuric iodide

14. Energy Changes in Matter
when any change occurs, energy is always involved
energy can be in different forms (light, heat, etc.)
energy is never destroyed or created (law of conservation of energy)

15. Energy Changes in Matter
Exothermic Reaction- reaction that gives off energy (feels warm on outside)
Endothermic Reaction- reaction that uses up energy (feels cold on outside)

16. Go on to Classification of Matter