1. Basics of Matter

2. Elements All matter is made of one or more elements
Elements are substances that can’t be separated into simpler substances
There are over 100 different elements
Human body is mostly : carbon, hydrogen, oxygen, nitrogen, phosphorus and sulfur

3. Chemical Symbols Each element has its own symbol
The symbol can be 1 or 2 letters
Examples: C = Carbon Au = Gold (Aurem)

4. Atoms An atom is the smallest piece of an element
Each element is made out of a different type of atom
Atoms are the simplest type of particle
An element’s properties depend on the structure of its atoms

5. Compounds Most elements are found as part of a compound
A compound is two or more elements that have chemically combined
Water is a compound, not an element.
It can be separated into hydrogen and oxygen

6. Electrolysis of Water

7. Molecules Water is made from particles called molecules – not atoms
A molecule is a particle made of two or more atoms that are chemically bound together
Every water molecule has 2 hydrogen atoms bonded to an oxygen atom
Some elements are molecular

8. Atoms and molecules are the “particles” that make up all matter

9. Chemical Formulas A chemical formula tells you:
which elements are present in a substance
how many atoms of each element
Example: Sugar C12H22O11
Sugar has: 12 atoms of Carbon
22 atoms of Hydrogen
11 atoms of Oxygen

10. Element or Compound? Which is the element and which is the compound?
Co or CO
How do you know?
How many elements are in the compounds below?
Fe2O3 RbBr HCN H2SO4

11. How many atoms?
How many atoms are represented in each of the following chemical formulas?
As2O5
SeO2
AgNO3
Na2S
Ca(OH)2
(NH4)2SO4