Ionic Compounds Nomenclature

Introduction We use the periodic table to tell us the most commonly expected charges for the ions of elements. For example: Group 1 (1A) elements have a 1+ charge. Na becomes Na + Group 2 (2A) elements have a 2+ charge. Mg becomes Mg 2+ Group 13 (3A) elements have a 3+ charge. Al becomes Al 3+ For example: Group 1 (1A) elements have a 1+ charge. Na becomes Na + Group 2 (2A) elements have a 2+ charge. Mg becomes Mg 2+ Group 13 (3A) elements have a 3+ charge. Al becomes Al 3+

Introduction We use the periodic table to tell us the most commonly expected charges for the ions of elements. For example: Group 15 (5A) elements have a 3- charge. N becomes N 3- Group 16 (6A) elements have a 2- charge. O becomes O 2- Group 17 (7A) elements have a 1- charge. Cl becomes Cl - For example: Group 15 (5A) elements have a 3- charge. N becomes N 3- Group 16 (6A) elements have a 2- charge. O becomes O 2- Group 17 (7A) elements have a 1- charge. Cl becomes Cl -

Forming Ionic Compounds We form ionic compounds by matching the charges of the ions to form a neutral compound. For example: Combining Na + with Cl - gives NaCl. Combining Ca 2+ with S 2- gives CaS. Combining Ga 3+ with N 3- gives GaN. Each of these combinations gives a neutral compound. For example: Combining Na + with Cl - gives NaCl. Combining Ca 2+ with S 2- gives CaS. Combining Ga 3+ with N 3- gives GaN. Each of these combinations gives a neutral compound.

Forming Ionic Compounds More complex combinations of ions also need to be balanced to produce neutral compounds. For example: Combining Na + with O 2- gives Na 2 O. Combining Ca 2+ with Br - gives CaBr 2. Combining Al 3+ with F - gives AlF 3. Each of these combinations gives a neutral compound. For example: Combining Na + with O 2- gives Na 2 O. Combining Ca 2+ with Br - gives CaBr 2. Combining Al 3+ with F - gives AlF 3. Each of these combinations gives a neutral compound.

Forming Ionic Compounds For even more complex combinations of ions we use a trick to produce neutral compounds. For example: Combining Ca 2+ with N 3- : For example: Combining Ca 2+ with N 3- : Ca 2+ N 3- To find the proper number of Ca 2+, we use the 3 of the N 3-. To find the proper number of N 3-, we use the 2 of the Ca 2+. To find the proper number of Ca 2+, we use the 3 of the N 3-. To find the proper number of N 3-, we use the 2 of the Ca CaN We can use this “criss-cross” when ever we have a complex combination of ions.

Binary Ion Nomenclature When we name binary ionic compounds (ionic compounds made from the ions of two elements), we name the cation first followed by the anion. In general, cations that are metals are given the name of the elemental metal. NaCl is named sodium chloride. BaF 2 is named barium fluoride. Ca 3 P 2 is named calcium phosphide. In general, cations that are metals are given the name of the elemental metal. NaCl is named sodium chloride. BaF 2 is named barium fluoride. Ca 3 P 2 is named calcium phosphide.

Binary Ion Nomenclature When we name binary ionic compounds (ionic compounds made from the ions of two elements), we name the cation first followed by the anion. In general, anions are given the name of the element followed by the suffix “-ide.” NaCl is named sodium chloride. BaF 2 is named barium fluoride. Ca 3 P 2 is named calcium phosphide. In general, anions are given the name of the element followed by the suffix “-ide.” NaCl is named sodium chloride. BaF 2 is named barium fluoride. Ca 3 P 2 is named calcium phosphide.

Binary Ion Nomenclature The single element anions are: CNOF PSCl SeBr I As fluoride chloride bromide iodide sulfide oxide selenide nitride phosphide arsenide

Binary Ion Nomenclature Transition (d-block) metals most commonly have a 2+ charge. ScTiVCrMnFeCo Ni Cu Zn YZrNbMoTcRuRh Pd Ag Cd LuHfTaWReOsIr Pt Au Hg LrRfDbSgBhHsMt Ds Rg Uub Ti 2+ Sc 2+ Mo 2+ There are exceptions to this rule. There are exceptions to this rule. Some transition and main group metals have two or Some transition and main group metals have two or more common charges. V 2+, V 3+, V 4+ Cr 2+, Cr 3+ Mn 2+, Mn 3+ Fe 2+, Fe 3+ Co 2+, Co 3+ Cu +, Cu 2+ Ga In Tl Sn PbBiPo Pb 2+, Pb 4+ Sn 2+, Sn 4+ Zn 2+ Ag + Au +, Au 3+

Binary Ion Nomenclature Since these cations can have different charges, we need a nomenclature that will distinguish between the different cations. The Stock system is used to identify different ions. We use the element name followed by the charge of the ion in parenthesis. For example: Cu + is written as copper(I) Cu 2+ is written as copper(II) Pb 2+ is written as lead(II) Pb 4+ is written as lead(IV) Since these cations can have different charges, we need a nomenclature that will distinguish between the different cations. The Stock system is used to identify different ions. We use the element name followed by the charge of the ion in parenthesis. For example: Cu + is written as copper(I) Cu 2+ is written as copper(II) Pb 2+ is written as lead(II) Pb 4+ is written as lead(IV)

Binary Ion Nomenclature Examples of Stock nomenclature: CuCl = copper(I) chloride CuCl 2 = copper(II) chloride FeO = iron(II) oxide Fe 2 O 3 = iron(III) oxide PbS = lead(II) sulfide PbS 2 = lead(IV) sulfide VO = vanadium(II) oxide V 2 O 3 = vanadium(III) oxide VO 2 = vanadium(IV) oxide Examples of Stock nomenclature: CuCl = copper(I) chloride CuCl 2 = copper(II) chloride FeO = iron(II) oxide Fe 2 O 3 = iron(III) oxide PbS = lead(II) sulfide PbS 2 = lead(IV) sulfide VO = vanadium(II) oxide V 2 O 3 = vanadium(III) oxide VO 2 = vanadium(IV) oxide

Polyatomic Ion Nomenclature Polyatomic ions are single ions that are made up of several atoms. Examples of polyatomic ions include: nitrate: NO 3 - sulfate: SO 4 2- phosphate: PO 4 3- ammonium: NH 4 + nitrite: NO2 - hydroxide: OH - dimercury: Hg 2 2+ acetate: CH 3 COO - Polyatomic ions are single ions that are made up of several atoms. Examples of polyatomic ions include: nitrate: NO 3 - sulfate: SO 4 2- phosphate: PO 4 3- ammonium: NH 4 + nitrite: NO2 - hydroxide: OH - dimercury: Hg 2 2+ acetate: CH 3 COO -

Polyatomic Ion Nomenclature Each of these units acts as a single ion. Nitrate (1-)acts in the same manner as chloride. Sodium nitrate is NaNO 3. Calcium nitrate is Ca(NO 3 ) 2. Aluminum nitrate is Al(NO 3 ) 3. Sulfate (2-) acts in the same manner as oxide. Sodium sulfate is Na 2 SO 4. Calcium sulfate is CaSO 4. Aluminum sulfate is Al 2 (SO 4 ) 3. Phosphate (3-) acts in the same manner as nitride. Sodium phosphate is Na 3 PO 4. Calcium phosphate is Ca 3 (PO 4 ) 2 Aluminum phosphate is AlPO 4. Each of these units acts as a single ion. Nitrate (1-)acts in the same manner as chloride. Sodium nitrate is NaNO 3. Calcium nitrate is Ca(NO 3 ) 2. Aluminum nitrate is Al(NO 3 ) 3. Sulfate (2-) acts in the same manner as oxide. Sodium sulfate is Na 2 SO 4. Calcium sulfate is CaSO 4. Aluminum sulfate is Al 2 (SO 4 ) 3. Phosphate (3-) acts in the same manner as nitride. Sodium phosphate is Na 3 PO 4. Calcium phosphate is Ca 3 (PO 4 ) 2 Aluminum phosphate is AlPO 4.

Polyatomic Ion Nomenclature Cations: Cations: ammonium: NH 4 + dimercury: Hg 2 2+ Anions: Anions: nitrate: NO 3 - nitrite: NO 2 - cyanide: CN - hydroxide: OH - perchlorate: ClO 4 - chlorate: ClO 3 - chlorite: ClO 2 - hypochlorite: ClO - acetate: CH3COO - hydrogen carbonate: HCO 3 - sulfate: SO 4 2- sulfite: SO 3 2- carbonate: CO 3 2- chromate: CrO 4 2- dichromate: Cr 2 O 7 2- silicate: SiO 3 2- oxalate: C 2 O 4 2- phosphate: PO 4 3- phosphite: PO 3 3-

Polyatomic Ion Nomenclature When we form ionic compounds from polyatomic ions, we treat the polyatomic ions as individual units of charge. When we form ionic compounds from polyatomic ions, we treat the polyatomic ions as individual units of charge. Ba 2+ (NO 3 ) - We use the criss-cross trick to find the formula of the compound. Ba(NO 3 ) 2 For example: For example: barium 2+ and nitrate 1- barium 2+ and nitrate 1- barium nitrate

Polyatomic Ion Nomenclature When we form ionic compounds from polyatomic ions, we treat the polyatomic ions as individual units of charge. When we form ionic compounds from polyatomic ions, we treat the polyatomic ions as individual units of charge. (NH 4 ) + (SO 4 ) 2- We use the criss-cross trick to find the formula of the compound. (NH 4 ) 2 SO 4 For example: For example: ammonium 1+ and sulfate 2- ammonium 1+ and sulfate 2- ammonium sulfate

Knowledge Check Determine the formulas of the following compounds: 1. sodium carbonate 2. copper(II) sulfate 3. lead(IV) phosphate 4. aluminum nitrite 5. ammonium sulfide Determine the formulas of the following compounds: 1. sodium carbonate 2. copper(II) sulfate 3. lead(IV) phosphate 4. aluminum nitrite 5. ammonium sulfide Na 2 CO 3 CuSO 4 Pb 3 (PO 4 ) 4 Al(NO 2 ) 3 (NH 4 ) 2 S Na + (CO 3 ) 2- Cu 2+ (SO 4 ) 2- Pb 4+ (PO 4 ) 3- Al 3+ (NO 2 ) - (NH 4 ) + S 2-

Knowledge Check Determine the names of the following compounds: 1. Fe 2 (CrO 4 ) 3 2. VO 2 3. Cr(CH 3 COO) 2 4. AuPO 4 5. NaClO Determine the names of the following compounds: 1. Fe 2 (CrO 4 ) 3 2. VO 2 3. Cr(CH 3 COO) 2 4. AuPO 4 5. NaClO iron(III) chromate vanadium(IV) oxide chromium(II) acetate gold(III) phosphate sodium hypochlorite