1. Water How can water be physically changed?
How can water be chemically changed?

2. Chemical Change
any change in which a new substance is formed with new physical properties.
This involves breaking bonds and forming new ones with other elements
Evidence: Release of energy as heat and light, change in colour, formation of gas, change in odour, etc.

3. Physical Change
breaking the attraction forces between adjacent molecules so that they are more spread apart
Simply put, it is a phase change where no new substance is made

4. Changes in Water
Chemical Change
Physical Change

5. Types of Chemical Reactions

6. Types: Synthesis
Example C + O2 O C + O C
General: A + B AB

7. Types: Decomposition
Example: NaCl Cl Na Cl + Na
General: AB A + B

8. Types: Decomposition 2 2 General: AB A + B Example: NaCl + Cl Na Cl Na

9. Decomposing Molten NaCl

10. Types: Decomposition
Example HgO O Hg
General: AB A + B

11. Types: Decomposition
2HgO 2Hg + O2 O Hg Hg O +
General: AB A + B

12. Types: Single replacement
Example: CuCl2 + Zn Zn Cl Cu + Cl Zn Cu +
General: AB + C AC + B

13. Types: Double displacement
Example: Pb(NO3)2 + KI
NO3 I
NO3 Pb K +
General: AB + CD AD + CB

14. Types: Double replacement
Example: Lithium sulfide + Zinc Fluoride