Two types of matter:

Mixtures Pure substances

Mixtures:

Consists of two or more substances that are mixed together but not chemically combined Ex: pre-baked cookies

Solution – liquid mixture Soda; sea water

2 types of mixtures Homogeneous – uniform composition

Heterogeneous – not uniform composition

Pure Substances Is made of only one kind of matter and has

definite properties. Ex: sugar, salt, gold, iron

Elements – are pure substances that cannot be broken down anymore. Look at periodic table

Compounds – is a pure substance formed from chemically combining two or more different elements H2O, CO2, C6H12O6

Atoms – smallest particle of a element

States of Matter Notes

A sheet of paper is about 10,000 atoms thick.

There are 2000 billion billion atoms of oxygen in one drop of water (double that for hydrogen)! A sheet of paper is about 10,000 atoms thick.

There are 2000 billion billion atoms of oxygen in one drop of water (double that for hydrogen)!

Atoms are held together by a chemical bond.

A molecule is a group of atoms that are joined together and act as a single unit. For example, H2O is made up of 2 hydrogen atoms and 1 oxygen atom and is VERY different from hydrogen alone or oxygen alone.

There are 3 atoms in one molecule of water.

Pure Substances

4 states of matter:

SolidsLiquidsGasses

4th State of Matter is Plasma. Just be aware of it…

Solids:

have a definite volume and a definite shape.

will keep that volume and shape in any position and in any container.

Particles in a solid are packed very tightly together and stay in fixed positions. These particles do move back and forth slightly—like balls connected by tight springs.

Crystalline solids-- particles form regular, repeating patterns.

e.g. salt, sugar, sand.

Amorphous solids—no pattern to particles.

e.g. Butter, glass, plastic, rubber.

Liquids:

have no shape of their own, but do have a definite volume.

takes shape of container.

Particles in a liquid are packed tightly together but they move around each other freely.

Viscosity:

- the resistance of a liquid to flowing.

More viscous = more “thick”.

Gases: have no definite shape or volume. can change volume easily. Particles in a gas fly at high

speeds in all directions, filling all the space available to them. They can be spread out to “fill” any space or they can compact together in a smaller space.

Draw this

Characteristics Properties

Properties for a given substance that never change. (always remain the same) water freezes at 32 degrees boils at 212

Physical Changes – alter the form of a substance Boiling Point

Melting point

Chemical Changes – one or more substances combine or break apart to form new substance Wood being burnt. Burning in general