NOMENCLATURE RULES

 

NOTE:

YOU WILL ONLY WRITE IUPAC NOMENCLATURE IN THIS CLASS

 

THE INSTRUCTOR CAN PROVIDE EITHER SYSTEM FOR NAMING.

 

 

 

Description

 

 

Rule

 

Example

 

Type I

Metal + Nonmetal

(Metal only has one type of charge)

 

 

1.  Always write cation then anion.

 Cation = metal with (+) charge.

Anion = nonmetal with (-) charge.

2.  Hydrogen can be anion or cation. 

3.  Name cation as noted on periodic table.

4.  Change anion name, add “ide” suffix.

5.  # (+)  charges = # (-) charges

6.  This is an ionic bond.

 

LiCl  = lithium chloride

BaO = barium oxide

MgCl2 = magnesium chloride

 

Type II a

Metal + Nonmetal

(Metal has more than one type of charge)

 

 

1.  Same rules as with Type I.

2.  Tell charge on metal by using Roman Numbers in ( ).  (I = +1 charge on metal; II = +2 charge on metal, etc…)

3.  This is ionic bonding.

 

 

Fe2O3 = iron (III) oxide  (IUPAC System)

                          or

                ferric oxide  (Classical System)

 

CuF = copper (I) fluoride 

            (IUPAC System)

                      or

            cuprous fluoride 

          (Classical System)

 

Type II b

Metal + Polyatomic Ion

(Metal has only one type of charge)

 

 

1.  Name the cation (metal) first.

2.  Then name the polyatomic ion

3.  If more than one polyatomic ion, put it in ( ) and then tell how many as subscript after ( ).

4.  Covalent bonding holds the polyatomic ion together.

 

NaNO3 = sodium nitrate

Mg(OH)2 = magnesium hydroxide

Ba(NO3)2 = barium nitrate

Ca(HCO3)2 = calcium hydrogen carbonate

                               (IUPAC System)

                                         or

                         calcium bicarbonate

                            (Classical System)  

 

     

 

Type II c

Metal + Polyatomic Ion

(Metal has more than one type of charge)

 

1.  Name the cation (metal) first but follow rules as listed in Type II above.

2.  Follow rules as in Type III a.  If more than one polyatomic ion, put it in ( ) and tell how many as a subscript after ( ).

3.  This is ionic bonding between metal and polyatomic ion.

4.  Covalent bonding holds the polyatomic ion together.

 

 

Cu2SO4 =  copper (I) sulfate (IUPAC System)

                                 or

                   cuprous sulfate (Classical System)

 

Ni3(PO4)2 =  nickel (II) phosphate

                            (IUPAC System)

                                      or

           nickelous phosphate(Classical System)                          

 

Type II d

Polyatomic Ion + Polyatomic Ion

(NH4+  = ammonium ion)

 

 

1.  Name polyatomic ions as memorized.

2.  Place ( ) around polyatomic ion ONLY IF more than one, then tell how many as subscript outside ( ).

3.  This is ionic bonding between metal and polyatomic ion.

4.  Covalent bonding holds the polyatomic ion together.

 

NH4ClO= ammonium  hypochlorite

 

(NH4)2SO3 = ammonium sulfite

 

 

 

Type II e

Polyatomic Ion + Nonmetal

 

1.  Name polyatomic ion them nonmetal,

2.  Nonmetal name is changed to the “ide” suffix since it is the anion.

 

 

NH4F  = ammonium fluoride

(NH4)2O = ammonium oxide

 

Type III

Nonmetal + Nonmetal

 

1.  Name as though ionic, even though it is not.  This is covalent bonding.

2.  Do not try to solve using metal + nonmetal rules.  JUST NAME IT USING GREEK PREFIXES.

mono =1, di=2, tri=3, tetra =4,

penta =5, hexa =6, hepta =7, octa =8, nona =9 deca =10

3.  Never use mono for the first element.

 

SO3 = sulfur trioxide

P2O5 = diphosphorus pentoxide

 

Acids & Bases

 

 

1.  Acids have H written first in the formula.  These are the transferable hydrogens.  Acids should be denoted by the (aq) state.  Acids without oxygen are named hydro___ ic acid.  Acids with oxygen are named by looking at the ending of their polyatomic names.  If “ate”, then “___ic  acid” and if “ite”, then “___ous acid”.  Hydro is not used with acids with oxygen in it.

2.  Bases can be easily recognized when the hydroxide ion (OH-) is observed.  Ammonia (NH3) is also a base.

 

HCl (aq)  =  hydrochloric acid

 

H2SO4 (aq) = sulfuric acid

 

HNO2 (aq) = nitrous acid

 

HYDRATES

(hydrate =  H2O associated with complex)

 

1.  Name the compound as noted above.

2.  Tell how many hydrates using Greek prefixes. 

3.  Place a dot ( . ) between complex and hydrate.

3.  Mono is used to indicate only one hydrate.

 

NaNO3 . H2O  =  sodium nitrate monohydrate

 

Sn(ClO3) . 5 H2O =tin (II) chlorate pentahydrate

                                (IUPAC System)

                                                        or

                     stannous chlorate pentahydrate

                               (Classical System)

 

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