Periodic Table NotesPeriodic Table Notes

ProtonsProtons

Protons found in nucleus of Protons found in nucleus of atomatom

Positive chargePositive charge Number of Protons determine Number of Protons determine

atomic number of atomatomic number of atom

NeutronsNeutrons

• Found in nucleus of atom• Neutral= Proton with an Electron

smashed into it• As an atom decomposes the Neutron

breaks into the Proton and Electron. • Protons + Neutrons =atomic weight of

atom• Isotopes are same element but different

number of Neutrons

Electrons

• Electrons revolve around the nucleus of atom.

• Negative charge. Very small particles.

• Chemical reactions occur using electrons.

• In atoms electron number equal proton number.

Periodic TableBack cover of textbook Period- across periodic table. Tells how

many shells of Electrons are present. Group- down periodic table. Groups are

elements that have similar valence shells of electrons.

Group 18 noble gases have all shells filled (non-reactive)

Group 17 is short one electron and is very reactive.

Group I has an extra electron and is also very reactive.

Atoms have Atoms have No charge- No charge- equal equal number of Protons and number of Protons and Electrons. The smallest unit of Electrons. The smallest unit of an Element that is still that an Element that is still that Element.Element.

Ions- Charged particles. Ions- Charged particles. Cations- positive ions with more Cations- positive ions with more

Protons than Electrons.Protons than Electrons. Anions- negative ions with more Anions- negative ions with more

Electrons than Protons.Electrons than Protons.

Chemical Bonds termsChemical Bonds terms

Elements- Pure substances made up of Elements- Pure substances made up of only one type of atomonly one type of atom

Compounds- Substances made of more Compounds- Substances made of more than one type of atomthan one type of atom

Molecule- Substance made of more than Molecule- Substance made of more than one atom. Can be the same element. one atom. Can be the same element. Ex. O2 or CO2Ex. O2 or CO2

Chemical bonds- inter atom connectionsChemical bonds- inter atom connections Covalent Bonds- Shared electronsCovalent Bonds- Shared electrons Ionic Bonds- gain or loss of electronsIonic Bonds- gain or loss of electrons Hydrogen Bonds- Polar attractions Hydrogen Bonds- Polar attractions

between atoms or moleculesbetween atoms or molecules