1. Mrs Teo CC Hwa Chong Institution

2. Video clip on heating iron and sulphur

3. 1. A compound has properties that are different from the properties of its constituent elements.

4. Video clip on burning magnesium in air

5. Video clip on burning sodium in chlorine

6. 2. When a compound is formed, energy (in the form of heat energy or light energy or both) is either taken in or given out to the surroundings.

7. 3. A compound can only be broken down into simpler substances by chemical methods, such as decomposition by heat energy, exposure to light or passing an electric current through it.

8. 4. The different elements in a compound always combine in a fixed proportion by mass. For example, 1 g of hydrogen combines with only 8 g of oxygen to form 9 g of water.

9. Some Examples of Compounds Sodium + Chlorine Hydrogen + Oxygen Carbon + Hydrogen + Oxygen Calcium + Carbon + Oxygen sodium chloride Water sugar Limestone (calcium carbonate)

10. A compound is a substance consisting of two or more elements chemically combined. What is a Compound?

11. Video clip on mixing iron and sulphur

12. 1. A mixture has the properties of its components.

13. Some Examples of Mixtures air soil blood sea water

14. 2. When a mixture is produced, little or no energy is given out or taken in.

15. 3. A mixture can be separated into its components by physical means such as evaporation, filtration, distillation or using a magnet

16. 4. The components in a mixture can be mixed in any proportion.

17. What is a Mixture? A mixture consists of two or more substances not chemically combined. What is a Mixture? A mixture consists of two or more substances not chemically combined.

18. Word Equations are commonly used for representing chemical reactions. e.g. 1. 1. iron + sulphur iron sulphide 2. magnesium + oxygen magnesium oxide 3. sodium + chlorine sodium chloride

19. Word Equations are commonly used for representing chemical reactions. 5. iron + hydrochloric acid hydrogen + iron(II) chloride 4. oxygen + hydrogen water 6. magnesium + hydrochloric acid hydrogen + magnesium chloride

20. Video clip on reaction between 1. iron and sulphur 2. calcium and water The End