1. Chemical Properties and Chemical Changes
Ms. Petrauskas

2. Chemical Change
Chemical changes occur when a substance combines with another to form a new substance, called synthesis or, alternatively, decomposes into two or more different substances.
These processes are called chemical reactions and, in general, are not reversible except by further chemical reactions.

3. Chemical Change is for Creating something new
Creating new and desirable products is a reason for having chemical reactions
Ex. Baking soda causes cakes to rise
Ex. Jewelry cleaner/ silver cleaner
Ex. Combustion of gasoline

4. SIGNS OF CHEMICAL CHANGE

5. Chemical Change
Change in colour

6. Precipitate Forms

7. Change in odour

8. Bubbles/ Gas produced

9. Change in temperature/light

10. Chemical Property
A characteristic of a substance that is determined when the composition of the substance is changed and one or more new substances are produced
Ex. Resistance to paint removers, ability to burn, reactivity, and product formation

11. Chemical Properties
Combustibility: the ability of a substance to react with oxygen to produce carbon dioxide, water and energy
Eg. The combustion of gasoline allows a car to run

12. Flammability: how easily something will burn or ignite, causing fire or combustion

13. Chemical Properties
Corrosion: the reaction involving a metal and oxygen (O2 and H2O)
Example: Silver + oxygen =silver oxide
Example: Iron + oxygen = iron oxide (rust)

14. Reactivity Reactivity: ability to react with other substances
explosives : explode under heat or pressure
Alkali metals: explode in water
Peroxides: strong oxidizing agents

15. Chemical Properties
Reacts with acid: the ability to react with an acid.
Ex. Magnesium metal will react with acid to form bubbles of Hydrogen gas