Warm Up CaO NaF MgCl2 K2O Al2S3 Draw Lewis Dot Diagrams for the following ionic compounds: CaO NaF MgCl2 K2O Al2S3

Ionic Formulas and Naming Unit Five, Day One Kimrey 11 March 2013

Formulas for Ionic Compounds Ionic compounds will bond in a ratio that cancels their ion charge ALL compounds no matter what are neutral

Steps for Writing Formulas Find the charges of the elements. Find the simplest ratio needed to cancel out the charges. Write the ratio numbers as subscripts (ones do not get written!) Write the positive ion first followed by the negative ion. Make sure not to write the charges of the ions in the formula.

Those pesky polyatomics. Polyatomic is a group of bonded atoms that still has a charge. Same steps as binary compounds plus… 5. If a subscript is added to a polyatomic ion place the entire polyatomic in (). REMEMBER! Never ever change the subscripts in a polyatomic ion.

Examples Sodium and Hydroxide (OH-1) NaOH Lithium and sulfate (SO4-2) Li2SO4 Calcium and phosphate (PO4-3) Ca3(PO4)2 Ammonium (NH4+1) and fluorine NH4F

Naming of Ionic Compounds – 3 different types! Binary Compounds - Write the name of the first element then write the beginning of the second element plus –ide Example: NaCl = Sodium Chloride CaS MgF2

Type #2 Polyatomic compounds – Write the name of the first element plus the name of the polyatomic ion. Example: CaSO4 = Calcium Sulfate NaOH Mg(NO3)2

The last kind… Transition metal compounds – Write the name of the first element with the oxidation number (charge) in parenthesis then write the beginning of the second element plus –ide. Example: PbO = Lead (II) Oxide Mn2S Y3N2

Tips Anions (nonmetal ions) are the element names with –ide at the end. ex. Chloride, oxide, and fluoride Polyatomic ions never change their names. Metals not in column 1 or 2 must have roman numerals to show their charge.

Examples NaCl CuO LiOH PbSO4 Ca(NO3)2 Fe2O3

Review PbF2 Lead (II) Fluoride CuCl3 Copper (III) Chloride FePO4 Iron (III) Phosphate Ni(NO3)2 Nickel (II) Nitrate

Practice Name The Following Fe(OH)3 Iron (III) Hydroxide CoSO4 Cobalt (II) Sulfate NiF2 Nickel (II) Fluoride CuNO3 Copper (I) Nitrate Ca(OH)2 Calcium hydroxide Write the formulas for… Manganese (II) Nitrate Mn(NO3)2 Yttrium (III) Chloride YCl3 Nickel (II) Sulfate NiSO4 Magnesium Bromide MgBr2 Lead (IV) Sulfate Pb(SO4)2

Correct the following Names and write the formula Magnesium (II) Sulfate Magnesium Sulfate; MgSO4 Iron dichloride Iron (II) Chloride; FeCl2 Lead (IV) disulfide Lead (IV) Sulfide; PbS2 Potassium Hydroxide  ; KOH