1. Structure of the Atom

2. Chemical symbol- an abbreviated way to write the name of an element. Chemical symbol- an abbreviated way to write the name of an element. Ex: C= Carbon O= Oxygen Ex: C= Carbon O= Oxygen H= Hydrogen N= Nitrogen N= Nitrogen Al= Aluminum Au= Gold Al= Aluminum Au= Gold Pg. 556-557(Periodic Table) Pg. 556-557(Periodic Table)

3. Inside the Atom Inside the atom is the nucleus. The nucleus contains protons and neutrons while surrounding the nucleus are the electrons. Inside the atom is the nucleus. The nucleus contains protons and neutrons while surrounding the nucleus are the electrons.

4. Electron → (e - ) ← Electron (e - ) ← Protons & ← Neutrons (p + ) & (n 0 )

5. Protons has a positive charge. (p+) Protons has a positive charge. (p+) Neutrons has no charge. Neutrons has no charge. (n 0 ) Electrons has a negative charge. (e-) Electrons has a negative charge. (e-)

6. Since there are protons and neutrons in the atom, the net charge of the nucleus is positive. Since there are protons and neutrons in the atom, the net charge of the nucleus is positive. The nucleus contains most of the mass of the atom. The nucleus contains most of the mass of the atom.

7. The overall charge of the atom is neutral (no charge). The overall charge of the atom is neutral (no charge).

8. Atomic Number Atomic number- the number of protons in the nucleus of an atom. Atomic number- the number of protons in the nucleus of an atom. The number of protons equals the number of electrons. The number of protons equals the number of electrons.

9. Atomic Number, # of p + and e - Atomic# p + e - Oxygen=Hydrogen=Carbon=Aluminum=Gold=

10. Atomic Number, # of p + and e - Atomic# p + e - Oxygen=888 Hydrogen=111 Carbon=666 Aluminum=131313 Gold=797979

11. Atomic Mass Atomic Mass- The number of protons and neutrons. Atomic Mass- The number of protons and neutrons. Round atomic mass to nearest whole number. Round atomic mass to nearest whole number. To calculate the number of neutrons, subtract the atomic number from atomic mass. To calculate the number of neutrons, subtract the atomic number from atomic mass.

12. Calculate the number of neutrons Oxygen Carbon Boron Oxygen Carbon Boron p + &n o 161211 p + -8-6-5 n o 8 6 6 Atomic mass=(# of p + &n o ) Atomic number= (# of p + )

13. Electron Cloud- a region where the electrons move around. It surrounds the nucleus of the atom. Electron Cloud- a region where the electrons move around. It surrounds the nucleus of the atom.

14. Electrons close to the nucleus have low energy while electrons farther away have more energy. Electrons close to the nucleus have low energy while electrons farther away have more energy. Electrons are placed into energy levels. Electrons are placed into energy levels.

15. Energy Levels Energy LevelMax # of e - 12 28 38 418

16. Nucleus p + & n o e- e- e-e- ←3 rd = 8 e- ←2 nd = 8 e- ←1 st = 2 e-