Binary Ionic Compounds Monovalent and Multivalent
Ionic Compounds Binary Ionic compounds – Monovalent; metal present forms only 1 type of cation Na → Na 1+ Mg → Mg 2+ – Multivalent; metal present can form 2 or more different cations that have different charges. Cu → Cu 2+ Cu →Cu 3+ Cr → Cr 1+ Cr → Cr 2+
Rules for Naming Monovalent Binary Ionic Compounds 1.The cation is always named first and the anion second. 2.A monatomic cation takes its name from the element. Example; Na 1+ is called sodium in the names of compounds containing this ion. 3.A monatomic anion is named by taking the first part of the element name (the root) and adding –ide. Example; Cl 1- is called chloride. 4.Write the name of the compound by combining the names of the ions.
Examples of Naming 1. NaCl 2. KI 3. CaS 4. CsBr 5. MgO
Remember Compounds formed from metals and non- metals are ionic. In an ionic compound the cation is always named first. The net charge of an ionic compound is always zero.
Multivalent Binary Ionic Compounds Multi-valent metals(transition metals) with a monatomic non-metal. Gold can form Au 1+ and Au 3+. The name Gold chloride could be either AuCl or AuCl 3, but which one? Roman numerals are used to specify the charge on the cation. Except for Ag 1+, Cd 2+ and Zn 2+ which do NOT need a Roman numeral in the name even though they are transition metals.
Examples of Naming 1. Fe 2 O 3 2. CuCl 2 3. PbO 2 4. MnO 4 5. CrO 3
Does the compound contain a mono- or multi- valent cation? Monovalent Multivalent Name the cation, using the element name. Using the principle of charge balance, determine the cation charge. Include in the cation name a Roman numeral indicating the charge.
Naming Ionic Compounds that contain Polyatomic ions Polyatomic ions; charged entities composed of several atoms covalently(sharing e - ) bonded together. Most of them are oxyanions with varying number of oxygens in the formula.
Polyatomic ions- p. 109 IONNAMEIONNAME NH 4 + AmmoniumCO 3 2- Carbonate NO 2 1- NitriteClO 1- Hypochlorite NO 3 1- NitrateClO 2 1- Chlorite SO 3 2- SulfiteClO 3 1- Chlorate SO 4 2- SulfateClO 4 1- Perchlorate OH 1- HydroxideCr 2 O 7 2- Dichromate PO 4 3- PhosphateCrO 4 2- Chromate
Naming Ionic Compounds that contain Polyatomic ions. Pretty much the same rules as with binary ionic compounds but you use the Polyatomics name. Need to recognize that it is an ionic compound with a polyatomic. Need ( ) around polyatomics if there is more than 1
Binary Compound? NOYES Polyatomic ion or ions present? Use the Naming Strategy from p. 95 Use the polyatomic ion’s proper name in the name of the compound. YES
Examples 1.NH 4 SO 4 2.Na 2 CO 3 3.Zn 3 (PO 4 ) 2 4.Co(C 2 H 3 O 2 ) 2 5.SnSO 3 6.Pb(NO 3 ) 4
Examples 1.Ammonium oxide 2.Copper (II) Sulfate 3.Iron (II) nitrate 4.Cobalt (III) sulfite 5.Zinc permanganate 6.Silver nitrate 7.Cobalt (II) phosphate
Molecular/covalent Compounds Binary compounds that contain only NONMETALS share electrons to form a compound. Rules for naming molecular compounds; – The first element in the formula is named first, and the full element name is used. – The second element gets an –ide ending. – Prefixes are used to denote # of atoms present. – Mono is never used for naming the first element. – Concerning Vowels; No “ao”, no “oo” yes to “io”. Its monoxide; not monooxide Its pentoxide; not pentaoxide
Naming Acids When dissolved in water, certain molecules produce H + ions (protons). 2 types of Acids; Binary - hydrogen and a monatomic anion. Oxyacids – hydrogen and a polyatomic anion.
Naming Acids 1.If binary acid; the acid is named with the prefix hydro- and the suffix –ic to the root name for the element. 2.If oxyacid ( with a polyatomic); 1.If the polyatomic anion ends in –ate, then acid ends in –ic. 2.If the polyatomic anion ends in –ite, then acid ends in –ous. 3.No prefix of hydro-
Examples HCl is hydrochloric acid HBr is hydrobromic acid HI is hydroiodic acid HCN is hydrocyanic acid H 2 SO 4 is sulfuric acid H 2 SO 3 is sulfurous acid HNO 3 is nitric acid HNO 2 is nitrous acid H 3 PO 4 is phosphoric acid H 3 PO 3 is phosphorous acid
Metal cation Monovalent Use cation full name and anion with –ide end. Formula must be neutral. Subscripts tells how many to make neutral Metal cation Multivalent. Includes; Sn, Pb Bi. Does not Include; Zn, Ag, Cd Use cation full name with Roman # and anion with –ide end. Roman # in name NOT formula. Use math to determine charge of mutlivalent cation. IONIC All non-metals Use prefixes in name to tell how many. Mono- not needed for first element. Second element uses ALL prefixes, gets –ide ending. No “ao”, “oo” Two types; binary and oxy. Binarys get hydro- and –ide ending. All non-metals Oxys; “I ate something icky” Anion ends in –ate, acid ends in –ic Anion ends in –ite, acid ends in –ous COVALENT ACIDS