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VALENCE ELECTRONS

• Outer shell e- are involved in “bonding”

• Gain/lose/share

• # e- in atom =

• e- seem to be arranged in energy levels

• Highest energy level electrons

• Largest distance from + nucleus

• “A” group number = # valence electrons

• (“A” groups are “main” group elements)

FORMULAS FOR BINARY SALTS

• Ionic bonding

• Cation – Metals lose e- fairly easily

• Anions – Nonmetals attract e-

Pg 35-39

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CHARGE OF IONS

MAIN GROUP ELEMENTS

• Positive charge = + group number

• Negative charge = group # - 8

FORMULAS FOR COMPOUNDS

• Metal + Nonmetal

• Metal loses e- to non-metal

Na Cl

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HANDOUT PRACTICE

Name Cation Anion formula

Sodium bromide

Calcium iodide

Barium oxide

Aluminum chloride

Lithium nitride

Magnesium sulfide

Strontium fluoride

OTHER METALS

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• Iron (III) chloride

• Lead (IV) sulfide

• Lead (II) sulfide

• Cr2O3

• MnO2

All metals except Group IA, IIA, Al, Ag, Zn, Cd should

use RN in their names – these can all have variable

“oxidation” numbers (charges)

POLYATOMIC ION

• Note root/suffixes

• Group has the charge

• Covalent bonding within group

• Overall extra electrons or too few electrons

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• Sodium sulfate

• Calcium bicarbonate

• Ammonium phosphate

• Manganese (IV) oxide

• FeSO4 Fe2(SO4)3

• Sodium oxalate

Pg 137 – common compounds

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Homework – answers will be on bb

– but Please do the worksheet

before looking at the answers

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REVIEW NAMING