IONIC BONDS / Cations and Anions Cation – positive ions Transition Metals use Roman Numerals to tell you the ox # Anion – negative ions
Oxidation Numbers - indicated # of e’ lost, gained or shared. Ex. Oxidation number of chlorine is -1
Halogens will have an oxidation number of:
Alkaline earth metals will have an oxidation number of:
We will name binary compounds together Using pages Describe how to name cations and anions when they are by themselves
Naming Binary Ionic Compounds Write the name of the ionic compound, Ca 2 N 3. Write the name of the ionic compound, K 2 O.
What is the name of BeBr 2 ? 1.Boron bromine 2.Beryllium bromine 3.Bromide beryllide 4.Beryllium bromide 5.Beryllide bromide
Metals with Variable Charges Many transition metals can form more than one type of cation. For this reason, you must show the oxidation number in the name using Roman Numerals
Naming Binary Ionic Compounds with Transition Metal Cations Write the name of the ionic compound, Cu 2 O.. Write the name of the ionic compound, NiS.
What is the name for SnBr 2 ? 1.Bromide Tin 2.Tin Bromide 3.Tin (I) Bromide 4.Tin (II) Bromide 5.Tin (III) Bromide 6.Tin (IV) Bromide
What is the name for FeI 3 ? 1.Iron iodide 2.Iron (I) iodide 3.Iron (II) iodide 4.Iron (III) iodide
What is the name for MnS? 1.Manganese sulfide 2.Manganese (I) sulfide 3.Manganese (II) sulfide 4.Manganese (III) sulfide
Exceptions: Some of the transition metals have only one ionic charge: –Do not need to use roman numerals for these: –Silver is always 1+ (Ag 1+ ) –Cadmium and Zinc are always 2+ (Cd 2+ and Zn 2+ )
Writing Formulas for Binary Ionic Compounds Write the formula for barium iodide. Write the formula for sodium oxide. Write the formula for aluminum nitride. Write the formula for copper (I) sulfide.
Criss-Cross Method for Writing Formulas - You can write the oxidation number and criss-cross them as subscripts. - Note – if not in lowest terms you must reduce the subscripts (ex. Magnesium oxide) Al 3+ S = Al 2 S 3
What is the formula for aluminum bromide? 1.AlBr 2.AlBr 2 3.Al 3 Br 4.Br 3 Al 5.AlBr 3
What is the formula for magnesium oxide? 1.MgO 2.Mg 2 O 2 3.MgO 2 4.Mg 2 O 5.OMg
Write the formula for titanium (II) chloride. 1.TiCl 2.Ti 2 Cl 3.TiCl 2 4.Ti 2 Cl 2
Write the formula for tin (IV) oxide. 1.SnO 2.SnO 4 3.SnO 2 4.Sn 4 O 5.Sn 2 O
POLYATOMIC IONS Not all compounds are made of only 2 types of atoms poly – “many” Memorize the polyatomic ions from p. 170.
Tricks for Polyatomic Naming Perchlorateper+root+ate ClO 4 -1 chlorateroot+ateClO 3 -1 chloriteroot+iteClO 2 -1 Hypochloritehypo+root+iteClO -1 Prefixes and suffixes designate number of oxygens
Naming Polyatomic Ionic Compounds Polyatomic ionic compounds are named just like binary ionic compounds. Exception: be sure to enclose the polyatomic ion in parentheses before writing the subscript (only necessary if subscript is not 1). Ex. Barium hydroxide = Ba(OH) 2
Write the formula for Calcium Nitrate. 1.CaNO 2 2.Ca(NO 2 ) 2 3.Ca 2 NO 3 4.Ca 2 NO 2 5.Ca(NO 3 ) 2
Write the formula for Magnesium Phosphate. 1.MgPO 4 2.Mg 3 (PO 4 ) 2 3.Mg 4 (PO 3 ) 2 4.MgPO 3 5.Mg(PO 4 ) 2