 Chemistry is the study of matter and the transformations it undergoes.

 Matter is anything that takes up space and has mass.  Mass is the amount of matter in an object and its resistance to change in motion along a smooth and level surface.  Volume is the measure of the space occupied by the object.

1.Substances- are either:  a) elements simplest kind of matter ◦ cannot be broken down any simpler and still have properties of that element! ◦ all one kind of atom.

b) compounds are substances that can be broken down only by chemical methods when broken down, the pieces have completely different properties than the original compound. made of two or more atoms, chemically combined (not just a physical blend!)

2. Mixture- physical blend of at least two substances; have variable composition. Can be homogeneous or heterogeneous

Element Compound Mixture

◦ Particles of matter are always in motion. ◦ The kinetic energy (speed) of these particles increases as temperature increases.

 Solids ◦ very low Kinetic Energy ◦ fixed shape ◦ fixed volume ◦ have weight. ◦ take up space ◦ are held tightly and packed fairly close together ◦ they are strongly attracted to each other ◦ vibrate

 Liquids ◦ low Kinetic Energy ◦ particles can move around but are still close together ◦ take the shape of their container (variable) ◦ fixed volume ◦ some attraction between them ◦ movement is limited by attractions between particles ◦ Flows ◦ take the shape of their container. ◦ have weight and take up space.

 Gases ◦ high Kinetic Energy ◦ particles can separate and move throughout container ◦ variable shape, spread out to fill the entire space given ◦ variable volume ◦ have weight and take up space. ◦ have little attraction between particles

 Plasma ◦ very high Kinetic Energy ◦ particles collide with enough energy to break into charged particles (+/-) ◦ gas-like, variable shape & volume ◦ stars, fluorescent light bulbs, CRTs Lightning is a plasma.