2. By Liz LaRosa revised by Karen Meadows www.middleschoolscience.comwww.middleschoolscience.com 2009 Classifying Matter: Elements, Compounds, and Mixtures

3. Pure Substances A sample of matter that has definite chemical and physical properties.

4. Elements pure substance that cannot be separated into simpler substance by physical or chemical means.

5. Compounds Pure substance composed of two or more different elements joined by chemical bonds. Made of elements in a specific ratio that is always the same Has a chemical formula Can only be separated by chemical means, not physically

6. Mixtures A combination of two or more pure substances that are not chemically combined. substances held together by physical forces, not chemical No chemical change takes place Each item retains its properties in the mixture They can be separated physically Chem4kids.com

7. Mixtures vs. Compounds http://www.bbc.co.uk/schools/ks3bitesize/science/chemistry/elements_com_mix_6.shtml

8. Can you identify the following? You will be shown a series of photos. Tell if each photo represents an item composed of an element, compound, or mixture. Review: An element contains just one type of atom. A compound contains two or more different atoms joined together. A mixture contains two or more different substances that are only physically joined together, not chemically. A mixture can contain both elements and compounds.

9. Element, Compound, or Mixture? Rocks

10. Element, Compound, or Mixture? Rocks

11. Element, Compound, or Mixture? Copper

12. Element, Compound, or Mixture? Copper

13. Element, Compound, or Mixture? Jelly Beans

14. Element, Compound, or Mixture? Jelly Beans

15. Element, Compound, or Mixture? Table Sugar

16. Element, Compound, or Mixture? Table Sugar

17. Element, Compound, or Mixture? Diamond

18. Element, Compound, or Mixture? Diamond

19. Element, Compound, or Mixture? Tea

20. Element, Compound, or Mixture? Tea

21. Element, Compound, or Mixture? Salt

22. Element, Compound, or Mixture? Salt

23. Element, Compound, or Mixture? Neon Gas

24. Element, Compound, or Mixture? Neon Gas

25. Element, Compound, or Mixture? Salad

26. Element, Compound, or Mixture? Salad

27. Element, Compound, or Mixture? Pure Water

28. Element, Compound, or Mixture? Pure Water

29. Element, Compound, or Mixture? Aluminum

30. Element, Compound, or Mixture? Aluminum

31. Element, Compound, or Mixture? Lemonade

32. Element, Compound, or Mixture? Lemonade

33. Element, Compound, or Mixture? Silver

34. Element, Compound, or Mixture? Silver

35. Element, Compound, or Mixture? Sand

36. Element, Compound, or Mixture? Sand

38. Notes Detailed notes are located at: http://www.middleschoolscience.com/elements-compounds- mixtures-notes-isn.pdf Flow Chart: http://www.middleschoolscience.com/matter-flow-chart- isn.pdf

39. Mixtures A combination of 2 or more substances that do not combine chemically, but remain the same individual substances Can be separated by physical means Two Types: 1. Heterogeneous 2. Homogeneous

40. Heterogeneous Mixture “Hetero” means different Visibly different substances or phases (solid, liquid, gas) Suspension A special type of heterogeneous mixture A mixture of larger particles that eventually settle

41. Homogeneous Mixture “Homo” means the same Has the same uniform appearance and composition throughout Maintains one phase (solid, liquid, gas) Commonly referred to as solutions Example: Salt water

43. Methods of Separating Mixtures

44. Filtration can be used to separate an insoluble substance from a soluble substance

49. Evaporation can be used to separate a solute from the solvent in a solution

51. Evaporation of sea water to produce salt

52. Distillation allows the separation of a solvent from a solution

56. A separating funnel can be used to separate two liquids which are immiscible

57. Chromatography allows separation of different pigment colours

59. A magnet Can be used to separate a magnetic substance from a non-magnetic substance