1. Mrs. Trotter’s 8th Grade Science Class
Chemical Properties
Mrs. Trotter’s 8th
Grade Science Class

2. Chemical Properties
The characteristics of a substance that describe what will happen when it interacts with other substances.

3. All Clues! Chemical Change
A substance turns into one or more new substances that have DIFFERENT properties than the original substance.
gas produced
color changes
light produced
temperature changes
All Clues!

4. Chemical Reactions Baking soda + vinegar= carbon dioxide + salty water
reactants …. form…. products
Baking soda + vinegar= carbon dioxide + salty water

5. Remember what elements are made of…?
Atoms!
The smallest particles that
have the properties of an
element are called atoms!

6. Inside Atoms Nucleus- holds protons & neutrons protons are positive
Neutrons are neutral
Outside the nucleus we find electrons
-electrons are negative
- they swirl around the nucleus like bees in on a hive!

7. Electron Cloud Model
Electrons exist in fixed energy levels called electron shells
the lowest level can contain 2 electrons
the next level can hold up to eight electrons
all together they can have 7 energy levels
the highest level with electrons in it is called the outer shell

8. In chemical changes, protons and neutrons stay in the nucleus
BUT! Electrons in the outer levels like to jump to or are shared with the outer shell of other electrons.
When one or more electrons jump or shares with another atom BOOM! It becomes a compound!

9. the compound then has different properties than either of the original substances!
GET IT????
A chemical change forms substances that are different than the original substances !!!!!!! !!!!!!!!!!!!!!!???????????????????????????????????????? right?!!

10. You end up what you start with
Conservation of Mass
There is no overall increase or decrease in the quantity of the matter that is changing.
You end up what you start with

11. Types of Chemical Equations
There are many types of chemical equations and impossible to memorize them all.
Most reactions fit into one of four catergories that we will memorize.
Synthesis
Decomposition
Replacement
Combustion

12. Synthesis +
Two or more substances combine and form one compound

13. Decomposition + +
One compound breaks down and forms two or more substances

14. Single Replacement + + + +
One element replaces another element in a compound

15. Double Replacement + +
A chemical reaction in which a substance combines
with oxygen and releases energy