1. CHEMISTRY!

2. Chemistry - Video
Chemistry – The study of matter and changes in matter
Matter – Anything that has a mass and occupies space

3. Compounds – Two or more elements combined. Ex: H2O or NaCl

4. Element – Pure substance made from one sort of atom. Ex: H or O

5. Atom – The smallest unit of matter

6. Five parts to an atom:
Nucleus – the centre of the atom – contains neutrons and protons.
protons – Positive charge (+)
neutrons – No charge or neutral (0)
electrons – Negative charge (-)
Electron shell – the region around the nucleus where the electrons are found.

7. The Periodic Table

8. Pre-Periodic Table Chemistry …
…was a mess!!!
No organization of elements.
Difficult to find information.
Chemistry didn’t make sense.

9. Dmitri Mendeleev Father of the Periodic Table
WHAT HE DID…
Put elements in rows by increasing atomic weight
Put elements in columns by the way they reacted.
SOME PROBLEMS…
He left blank spaces for what he said were undiscovered elements.
He broke some patterns

10. A: Atomic number = number of protons
B: The elements charge
C: The elements symbol
D: The name of the element
E: Atomic Mass or the number of protons and neutrons

11. Atomic number - # of protons
Atomic Mass – Mass of protons and neutrons
So… how do you calculate the number of neutrons?
Atomic Mass – Atomic number = # of neutrons!
Number of Electrons equals the number of protons in a neutral atom.

12. P # 1, 3, 6, 7, 11-21