Two types of matter:
Mixtures Pure substances
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.
4 states of matter:
4th State of Matter is Plasma. Just be aware of it…
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.
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.
- 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.
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
Chemical Changes – one or more substances combine or break apart to form new substance Wood being burnt. Burning in general