Naming rules can follow IUPAC (modern) rules or common rules. All rules are IUPAC unless stated.

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1 Kailley1 NAMING AND FORMULA WRITING (INORGANIC COMPOUNDS) 2 basic types of compounds you know from Sc Ionic metal + nonmetal 2. Covalent nonmetal + nonmetal (NOTE:an ion is a charged atom,either + or ) Naming rules can follow IUPAC (modern) rules or common rules. All rules are IUPAC unless stated. IONIC COMPOUNDS. CREATING IONIC FORMULAS You must know the common charges for certain groups in periodic table. Memorize these columns: +1, +2, +3, +4, 3,2,1,0 STEPS: Examine name:

2 Kailley2 Full metal name + nonmetal stem name + ending i.e. potassium nitride From metal name, get symbol and charge for that metal. Most metals only have 1 charge,if it has more, the metal name will have a roman numeral in brackets giving the charge. i.e. Magneiusm : Mg 2+ iron (III) : Fe 3+ ammonium :NH + 4 (memorize it) ** metals always have positive charges, symbol is always written first From nonmetal name ENDING, determine formula and charge for nonmetal. o if the ending is ide then the symbol is directly from periodic table as is the charge

3 Kailley3 i.e nitride: N 3 oxide O 2 o if the ending is ate or ite then use DATA BOOKLET TABLE to determine formula and charge of this NON METAL polyatomic ion. i.e. nitrate NO 3 **NON metals always have negative charges, formula is always written second The overall charge on the whole compound must be zero, so adjust the number of metal and nonmetal atoms using subscripts so the total+ is = to the total. TIP:to show more than 1 polyatomic ion, use brackets around the whole

4 Kailley4 polyatomic formula, then a subscript. (SHORTCUT: to get the proper subscripts, swap the charge numbers and use as subscripts.eliminate the + /,then reduce the subscripts if necessary ie. potassium and oxygen: called potassium oxide K + O 2 swap charges to get subscripts K 2 O lead (IV) sulfide Pb +4 S 2 not a polyatomic ion PbS 2 reduce subscripts for ionic (Pb 2 S 4 XX) calcium nitrate Ca 2+ NO 3 group) need 2 NO 3 s (as a

5 Kailley5 Ca(NO 3 ) 2 put brackets to indicate more than 1 polyatomic ion. ie. Zinc Nitride ide = nonmetal = from P. table Zn 2+ N 3 Zn 3 N 2 Zinc nitrate ate or ite polyatomic ion Zn 2+ NO 3 1 Zn(NO 3 ) 2 Naming Ionic Compounds: identify the positive (metal) ion and negative (nonmetal) ion. Rules: METAL NAME: positive ion takes the same name as the element.

6 Kailley6 Use a roman numeral if one is used in data booklet, or if the element is a transition metal (few exceptions in data booklet given of transition metals that don t need a roman numeral) To determine charge on a transition metal, find the total negative charge coming from nonmetal, and the metal must balance that out. NON_METAL NAME: if its an single element from periodic table use stem name and add the ending ide COMMON STEM NAMES FOR NONMETALS: O: ox N: nitr S: sulf P: phosph F: fluor Cl: chlor

7 Kailley7 Br: brom I: iod if it s a polyatomic ion, use full name from the data booklet:some polyatomic ions have more than 1 name, use either one i.e. SO 2 4 : sulphate. HSO 4 :hydrogen sulphate ion CH 3 COO : acetate or ethanoate TRY THESE LiF lithium fluoride CaBr 2 calcium bromide AlCl 3 aluminum chloride KNO 3 PbI 2 : lead (II) iodide Cu 2 SO 4 : copper (I) sulfate Fe(NH 4 ) 2 : iron (II) pernitrate

8 Kailley8 Subsection: Advanced naming Of Polyatomic ions: TREND 1: Certain trends exist, can name ions not on data booklet. Use the following as guide (in data booklet) ClO 4 ClO 3 ClO 2 ClO perchlorate chlorate chlorite hypochlorite The difference in the names is due to difference NUMBER of O s. (NOTE charge is the same) Per has 1 more O than ate version. ite has 1 less O than ate hypo ite has 2 less O s than ate (which is 1 less O than ite ) Name these: NO 4

9 Kailley9 SO 2 2 Try these ie. Na 2 SO 4 : sodium sulfate Ca 3 (PO 4 ) 2 : calcium phosphate KNO 2 : potassium nitrite TREND 2:FAMILIES ClO 3 chlorate: so BrO 3 bromate (same family Cl and Br,so similar name and charge) Name of IO 3 BrO 4 IO IO 2

10 Kailley10 subsection: old naming system: (noniupac) to show which metal ion is used, you use the Latin name, with the ending: ous lower charge ic higher charge ie. Fe 2+ : iron (II) ferrous Sn: stannous stannic Fe 3+ : iron(iii) ferric Pb: plumbous plumbic SnO 2 : stannic oxide PbCl 2 : plumbous chloride Hydrate: sometimes water is attached to ionic compounds. ie. FeCl 2 * 3H 2 O

11 Kailley11 Rule: regular ionic compound name + prefix + hydrate. iron (II) chloride trihydrate CuCl * 4H 2 O chloride tetrahydrate Copper(I) Page: # 1215, 17, 18 Hydrides H is nonmetal, can tell because its written second in formula stem name is hydr ie. NaH Sodium hydride

12 Kailley12 Ionic Naming Subsection: Acids Acids are any ionic compounds which has hydrogen acting as the metal. I.e. HCl, HCN 2 basic types of acids, each with naming/formula writing rules,either use IUPAC or common, it will be stated BINARY ACIDS H + 1 type of nonmetal element i.e. HCl Rules IUPAC: follow ionic compound rules COMMON: hydro + stem name + ic acid **carbon and sulphurdon t have stem names in common acid naming, use

13 Kailley13 their full name, use phosphor for phosphorous** Formula HCl IUPAC hydrogen chloride Common hydrochloric acid Formula IUPAC Common H 3 P hydrogen phosphide hydrophosphoric acid OXO ACIDS H + polyatomic ion containing oxygen i.e. HNO 3 Rules: IUPAC: follow regular ionic rules COMMON: Only use polyatomic ion name (same exceptions with carbon,sulphur and phosphorous) and change ending as follows:

14 Kailley14 If name ends in ate change to ic acid If name ends in ite change to ous acid Examples: Formula IUPAC Common H 2 SO 4 hydrogen sulphate sulphuric acid HNO 2 hydrogen nitrite nitrous acid HNO hydrogen hyponitrite hyponitrous acid H 3 PO 5 hydrogen perphosphate perphosphoric acid Final Points The formulas of single metal atoms is the symbol on the periodic table The formula of ions, is the symbol with the charge. i.e. magnesium: Mg magnesium ion: Mg 2+

15 Kailley15 COVALENT COMPOUNDS Naming Use prefixes to describe the number of atoms of each element type present. Prefixes: 1mono 2di 3tri 4tetra 5penta 6hexa 7hepta 8octa 9nona 10 deca Write the prefix+ full name of the first nonmetal +prefix+stem name of second nonmetal+ ide NOTE:Only use the mono prefix for the second nonmetal, it is not needed for the first nonmetal. ie) C 3 N 2 : Tricarbon dinitride O 2 F 2 : Dioxygen Difluoride NO 3 :nitrogen trioxide NO 3 nitrate ion

16 Kailley16 CO carbon monooxide Writing Formulas: The prefixes indicate how many atoms of each element are present: sulfur trioxide SO 3 nitrogen dioxide NO 2 NOTE:the nonmetal that is furthest to the left and the nearest to the top of the periodic table is always written first. Diatomic Molecules Certain covalent molecules come in pairs, 7 of them H 2, N 2,O 2,F 2,Cl 2,Br 2,I 2 Can be named in several ways: i.e. H 2 hydrogen, hydrogen gas,hydrogen vapor.

17 Kailley17 Final Points The formula of elemental phosphorous is P 4 and sulphur is S 8 Memorize ammonia: NH 3 and water H 2 O