| A | B |
|---|
| pure substance | matter with a fixed, uniform composition |
| element | simplest substance |
| atoms | elements are made up of these |
| compound | two or more elements combined |
| mixture | compound with a varied composition |
| heterogeneous mixture | parts are visibly different |
| homogeneous mixture | parts appear the same |
| types of mixtures | solutions, suspensions, colloids |
| solution | substance substances dissolve into homo mixture |
| liquid solution properties | particles do not settle out, get trapped or scatter light |
| suspension | layered hetero mixture |
| property of suspensions | particles scatter light; cloudy |
| colloid | solution and suspension combined |
| physical property | characteristic of a material |
| examples of physical properties | viscosity, conductivity, hardness |
| viscosity | liquids resistance to flowing |
| higher viscosity | slower the liquid moves |
| conductivity | ability to allow flow of heat |
| malleability | ability to mold a solid |
| melting point | temperature when substance changes from solid to liquid |
| density | mass per unit volume |
| uses of physical properties | identify or choose materials |
| common separation methods | filtration & distillation |
| filtration | separating by particle size |
| distillation | separating by boiling point |
| physical change | properties change; not composition |
| chemical property | change in compositon of matter |
| types of chemical properties | flammability & reactivity |
| flammability | ability to burn |
| reactivity | substance chemically combine with another |
| evidence of chemical change | color change, gas produced & precipitates |
| precipitate | solid forms & separates from liquid mixture |
