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Nomenclature Names and formulas

Using Flow Charts

Ionic Formulas Ions combine in small, whole number proportions so that the sum of oxidation numbers will be zero! Cations retain the name of the element and always comes first. Anions keep the root name but add “ide” ending.

Examples… Lithium + chlorine magnesium + bromine Lithium Chloride aluminum + oxygen Lithium Chloride Magnesium Bromide Aluminum Oxide

Transition Metals Some of the transition metals have variable oxidation numbers. (They have more than one.) Roman numerals are used to indicate oxidation numbers for elements with variable oxidation states. Roman numerals are always positive!

Examples… Nickel (III) oxide Nickel (II) oxide Ni2O3 Fe2O3 FeO NiO Iron (III) Oxide Iron (II) Oxide

Polyatomic Ions a group of atoms that stay together and have one oxidation number. They combine like single atom ions, so that the total charge must be zero. No name change here

Examples… Na 1+ and SO4 2- Ca 2+ and OH1- NH4 1+ and O2- NH4 1+ and PO4 3- Sodium Sulfate Calcium Hydroxide Ammonium Oxide Ammonium Phosphate

POLYATOMIC IONS (charged building blocks) Polyatomic ions are mostly made of two non-metals. Ions with -1 charge perbromate BrO4-1 bromate BrO3-1 bromite BrO2-1 hypobromite BrO-1 perchlorate ClO4-1 chlorate ClO3-1 chlorite ClO2-1 hypochlorite ClO-1 periodate IO4-1 iodate IO3-1 iodite IO2-1 hypoiodite IO-1 nitrate NO3-1 nitrite NO2-1 hydroxide OH-1 cyanide CN-1 acetate C2H3O2-1 Permanganate MnO4-1 bicarbonate HCO3-1 Ions with a -2 Charge carbonate CO3-2 sulfate SO4-2 sulfite SO3-2 chromate CrO4-2 dichromate Cr2O7-2 oxalate C2O4-2 Ions with a -3 Charge phosphate PO4-3 phosphite PO3-3 arsenate AsO4-3 Ions with +1 charge ammonium ion NH4+1

Name Origins “ate” suffix most common bromate BrO3-1 “ite” suffix 1 oxygen less than “ate” bromite BrO2-1 “hypo” prefix 1 oxygen less than “ite” hypobromite BrO-1 “per” prefix 1 oxygen more than “ate perbromate BrO4-1

Name Covalent Bounds Covalent Bonds NO2 CO2 PO3 SF4 SO3 Between 2 or more non-metals NO2 CO2 PO3 SF4 SO3

Naming Molecules The least electronegative element comes first. Increases Left to Right Decreases top to bottom 2. A prefix is always used for the first and second element to indicate quantity and the suffix “ide” is applied

The ability of an atom to attract the electrons of another Electronegativity The ability of an atom to attract the electrons of another atom when bonded INCREASING DECREASING

Prefixes to Know 1 = mono 2 = di 3 = tri 4 = tetra 5 = penta 6 = hexa 7 = hepta (NEVER use the prefix Mono on the first element )

Examples… PCl3 NH3 P2O5 I4O7 SCl6 PO5 H2O phosphorus trichloride nitrogen trihydride diphosphorus pentoxide tetraiodine heptoxide sulfur hexachloride phosphorus pentoxide dihydrogen monoxide NH3 P2O5 I4O7 SCl6 PO5 H2O

Examples… CO2 CO SO3 N2O3 N2O5 AlCl3 Carbon Dioxide Carbon Monoxide Sulfur Trioxide Dinitrogen Trioxide Dinitrogen Pentaoxide Aluminum Trichloride