Unit 4 - Nomenclature Naming Binary Compounds that contain a metal and a nonmetal Naming Binary Compounds that contain only nonmetals Naming Compounds that contain Polyatomic ions Naming Acids Writing Formulas from Names Zumdahl pages 122-143

Unit 4 - Nomenclature Upon completion of this unit, you should be able to do the following:   Name binary compounds of a metal and nonmetal Name binary compounds containing only nonmetals Name common acids. Name compounds containing polyatomic ions Write the formula of a compound given its name

Naming Binary Compounds It is important to understand how compounds are named to be able to communicate in the world of chemistry. Binary compounds are composed of two elements. They can be divided into two classes: Compounds that contain a metal and a non-metal Compounds that contain two non-metals

Naming Binary Compounds When a metal such as sodium combines with a non-metal such as chlorine, the resulting compound contains ions. The metal loses one or more electrons to form a cation. The non-metal gains one or more electrons to form an anion. The resulting substance is called a binary ionic compound. These componds are named simply by using the names of the ions. NaCl is sodium chloride CaF2 is calcium fluoride

Naming Binary Compounds

Naming Binary Compounds Type I compounds – the metal forms only one cation. Type II compounds – the metal can form two (or more) cations that have different charges.

Naming Binary Compounds

Naming Binary Compounds More Type I Compound Examples Compound Ions Name KI K+ , I- potassium chloride CaS Ca2+ , S2- calcium sulfide LiBr Li +, Br- lithium bromide MgO Mg2+ , O2- magnesium oxide

Naming Binary Compounds Naming Type I Compounds Practice LiF AlCl3 MgI2

Naming Binary Compounds Many metals can form two (or more) cations that have different charges. For example, iron (Fe) can produce Fe2+ or Fe3+ cations. This means that if you saw the name iron chloride, you would not know if the compound was FeCl2 or FeCl3. Therefore we use Roman numerals to Specify the charge on the cation. So FeCl2 is iron (II) chloride and FeCl3 is iron (III) chloride.

Naming Binary Compounds Common Type II Cations Fe2+ iron (II) Fe3+ iron (III) Cu+ copper (I) Cu2+ copper (II) Co2+ cobalt (II) Co3+ cobalt (III) Sn2+ tin (II) Sn4+ tin (IV) Pb2+ lead (II) Pb4+ lead (IV)

Naming Binary Compounds Naming Type II Compounds Practice CuCl HgO Fe2O3 MnO2 PbCl4

Naming Binary Compounds Binary compounds that contain only nonmetals follow rules similar to those for naming binary ionic compounds.

Naming Binary Compounds Type III Compound Examples BF3 boron trifluoride NO nitrogen monoxide N2O5 dinitrogen pentoxide

Naming Binary Compounds Naming Type III Compounds Practice PCl5 P4O6 SF6 SO3 SO2 N2O3

Naming Polyatomic Ions Polyatomic ions are charged entities composed of several atoms bound together. See list on reverse side of periodic table handout Naming is similar to binary compounds, but you must learn to recognize polyatomic ions Name the cation first and then the anion. Use Roman numerals if the metal forms mutiple cations For this class, you do not need to memorize a list of polyatomic ions

Naming Polyatomic Ions

Compounds with Polyatomic Ions Example: NH4C2H3O2 Recognize that NH4 + is the ammonium polyatomic cation C2H3O2 - is the acetate polyatomic anion The compound is ammonium acetate.

Compounds with Polyatomic Ions Practice: Na2SO4 KH2PO4 Fe(NO3) 3 Mn(OH) 2 Na2SO 3 NH4ClO 3

Compounds with Polyatomic Ions In the list of polyatomic ions, notice that there are series of ions that contain a given element and different oxygen atoms. These are anions called oxyanions. When there are two members in such a series, the one with the smaller amount of oxygen is called –ite and the one with the larger amount of oxygen is called –ate. When there are more than two members of a series, hypo- (one less) and per- (one more) are used as prefixes. ClO- hypochlorite ClO2- chlorite ClO3- chlorate ClO4- perchlorate

Naming Acids When dissolved in water, certain molecules produce H+ ions. These substances are called acids. An acid can have one or more H + ion. The rules for naming acids depend on whether the anion contains oxygen. If the anion does not contain oxygen, the acid is named with the prefix hydro- and the suffix –ic attached to the root name for the element. HCl is hydrochloric acid. When the anion contains oxygen and ends in –ate, the suffix for the acid becomes –ic. H2SO4 is sulfuric acid. When the anion contains oxygen and ends in –its, the suffix for the acid becomes –ous. H2SO3 is sulfurous acid

Naming Acids HCl hydrochloric acid H C2H3O2 acetic acid Common Acids HCl hydrochloric acid H C2H3O2 acetic acid H2SO4 sulfuric acid HNO3 nitric acid H3PO4 phosphoric acid

Writing Formulas from Names You also need to be able to write the formula of a compound given the name. Again, you must be able to recognize polyatomic ions. Example: Calcium hydroxide Calcium has a charge of +2. Hydroxide is OH with a charge of -1. Two hydroxide ions are required to balance the charge on calcium, so the formula is Ca(OH)2

Writing Formulas from Names Practice: Potassium hydroxide Sodium carbonate Cobalt (III) nitrate Calcium chloride Lead (IV) oxide Dinitrogen pentoxide Ammonium perchlorate