| A | B |
|---|
| matter | anything that has mass and takes up space |
| chemistry | the study of matter and how it changes |
| substance | a single kind of matter |
| physical property | a characteristic of a substance that can be observed without changing it into another substance |
| chemical property | a characteristic of a substance that describes its ability to change into different substances |
| element | a pure substance that cannot be broken down into any other substances by physical or chemical means. It is made up of only one kind of atom. |
| atom | basic particle from with all elements are made. |
| chemical bond | the force of attraction between two or more atoms. |
| molecule | a group of two or more atoms held together by chemical bonds |
| compound | a group of tow or more elements that are chemically combined in a set ratio. |
| chemical formula | shows the elements in a compound and the number of atoms of each element in the compound |
| mixture | two or more substances that are in the same place but are not chemically bonded |
| heterogeneous mixture | a mixture where you can see the separate parts. |
| homogeneous mixture | a mixture where the substances are so evenly mixed that you can't see the separate parts. |
| filtration | separating a solid from a liquid by running it through filter paper |
| magnetic attraction | iron objects can be separated from a mixture using a magnet |
| evaporation | when left in the open air, liquid solutions can change to a ga, leaving the solid components behind |
| distillation | liquids can be separated from each other by heating them up to the temperature at which one boils. The liquid boils to a gas; the gas cools; the gas then forms a separate liquid. |
| weight | the force of gravity on an object |
| mass | the amount of matter in an object |
| volume | the amount of space an object occupies |
| density | mass/volume |
| physical change | alters the form or appearance of matter but does not create a new substance |
| chemical change | a change in matter that produces one or more new substances |
| law of conservation of mass | matter cannot be created or destroyed in a chemical reaction |
| temperature | how hot or cold something is |
| thermal energy | the total energy of the motion of all the particles in an object |
| endothermic reaction | a reaction where energy is absorbed. The temperature goes down. |
| exothermic reaction | a reaction where energy is release. The temperature goes up. |
