Chapter 2 Section 1

matter- anything that has mass and takes up space

mass- the amount of matter in an object

substance- matter with a definite and uniform composition

-contains only one type of matter

-substances have a chemical symbol or chemical formula

-ex- sugar (all sugar is C12H22O11)

-all identical substances have identical physical properties

physical property- quality of a substance that can be observed or measured without changing the composition

ex- color, odor, solubility, hardness, density, melting and boiling points

*can help identify a substance

-Page 29 Table 2.1

States of Matter

solid- matter with a definite shape and volume, particles are closely packed making it incompressible

liquid- matter that flows, has a fixed volume, and takes the shape of its container, incompressible

gas- matter that takes both the shape and volume of its container, easily compressible because particles are spaced very far apart

*gases are gases at room temperature

vapor- gaseous substance that is liquid or solid at room temperature

Types of Changes:

physical change- alters a given material without changing its composition

-described by words like cutting, grinding, bending

-are reversible

ex- carving wood, melting ice, stretching rubber band

chemical change- results in a change in chemical composition of a substance

-change is not reversible

-described by words like burn, rot, rust, explode

ex- wood burning, iron left out in the rain

Indications of a chemical change:

1) color change

2) odor change

3) gas/bubbles produced

4) heat absorbed or released

5) precipitate (solid) formed

6) light produced