Natural Science

4. a device with a magnetic needle that always points north. We use it to orient ourselves.
6. a type of matter which contains two or more pure substances.
7. a material which does riot allow electrical charges to move.
8. a chemical reaction that happens when objects or substances are burned.
10. an object which can attract other objects made of iron and other magnetic metals.
11. circuit a closed path through which electricity flows.
13. a method used to separate solids from liquids in homogeneous mixtures. fermentation a chemical reaction that happens in some living things. such as yeast and bacteria.
14. a method used to separate solids from liquids, or solids with different size particles, in heterogeneous mixtures.
15. these happen when atoms react and group together differently.
18. the component of an electnc circuit which provides the electricity.
19. the force of attraction exerted by magnets.
22. a mixture in which the different components cannot be distinguished.

1. the component of an electric circuit which transforms electricity into another type of energy.
2. another word for a homogeneous mixture.
3. a method used to separate liquids that have different boiling points in homogeneous mixtures.
5. a type of matter which contains only one type of component.
9. a chemical reaction that happens when some meta substances such as iron combine with oxygen in the presence of water.
12. a method used to separate substances of different density in heterogeneous mixtures.
16. a matenal which allows electrical charges to move.
17. a mixture in which the different components can be distinguished.
20. a connecting wire, usually made of copper. wrapped in plastic covering.
21. the flow of electncal charges through materials.