1. Elements, Compounds & Mixtures

2. GOAL To tell the difference between elements, compounds and mixtures and to give examples of each

3. Matter Matter is anything that has mass and takes up space. Matter is made up of many different things:

4. Substance A substance is a single kind of matter that has a specific composition and a specific set of properties - for example, color, melting point, texture...

5. Physical Properties Physical Properties are characteristics of substances that can be observed without changing it into another substance. Examples: freezing or melting density hardness color

6. Chemical Properties Chemical Properties are characteristics of pure substances that describe their ability to change in to different substances.

7. Chemical Properties Examples: Does it burn? (Flammability) Does it combine with oxygen? (Iron does and forms rust.) What will the substance react with?

8. Types of substances Elements Simplest, pure substance, one type of atom present –O 2, Na, Fe, N 2

10. Elements There are over 100 elements in the periodic table. Elements all have unique symbols: Hydrogen: H Lithium : Li Oxygen : O 2 Neon : Ne

11. Types of substances Compound 1. Made of several different atoms (combined by chemical reaction) –Salt- NaCl –Sugar- C 6 H 12 O 6 2. Different properties from the elements that make them up

12. Types of substances Mixtures 1. Made of more than one kind of molecule (many compounds) 2. Can be separated or pulled apart by physically (they are NOT chemically combined) 3. 2 types: –Heterogeneous –Homogeneous

13. Heterogeneous Mixtures You can see the different parts. Examples: Salad Soil Bowl of Mixed Nuts

14. Types of substances Heterogeneous Mixtures 1. Not the same throughout 2. Large easily seen particles that can be separated out 3. Heterogeneous liquid mixtures known as suspensions – Settles after standing 4. Tacos, salad, italian dressing, pebble/sand mixture

17. Homogeneous Mixture They are so evenly mixed, you can not see the individual parts. Examples: Salt dissolved in water Brass is a mixture of copper and zinc

18. Types of substances Homogeneous Mixtures 1. Appears same throughout 2. Well mixed 3. Won’t settle upon standing, 4. Tiny unrecognizable particles –Solutions are homogeneous mixtures

19. Types of substances Homogeneous Mixtures –Won’t settle out –Cloudy-Scatters light –Particles mix, don’t dissolve Milk, lotion, toothpaste

21. Types of substances Homogeneous Mixtures Metal Solutions a)Alloys- solid metal solutions b)Gold= copper and gold c)Brass= copper and zinc d)Sterling silver= silver and copper

22. Types of substances Homogeneous Mixtures Solutions a)One substance dissolved in another b)Tiny particles can’t be seen c)Best mixed d)Clear or transparent- light passes right through e)Ocean water, lemonade, air