1. 1 Intro to Inorganic Chemical Nomenclature Part 1, Binary Compounds This lesson was divided into two parts Part 1 Binary Compounds In this first video we are studying the nomenclature of Binary Compounds There is also a second video dealing with the nomenclature of Polyatomic Compounds. Youtube ‘Inorganic Chemical Nomenclature Part 2 Polyatomic Compounds’

2. Intro to Inorganic Chemical Nomenclature Part 1 Binary Compounds Chemical Nomenclature = writing the formulas and names of chemicals. Using three systems of inorganic nomenclature … the Stock system the Prefix system the Ous-Ic system This requires that you learn the names, formulas and oxidation numbers (Ox #’s) of a variety of monatomic elements and polyatomic ions needed for binary and polyatomic compounds. This lesson is designed for a 1 st semester college chemistry student and assumes that the student already has a working knowledge of electron configuration, electronegativity, chemical bonding, and acid ionization. 2

3. Intro to Inorganic Chemical Nomenclature Chemical Formulas of Binary Compounds: Binary compounds are made of two different kinds of atoms. A chemical formula tells us which atoms and how many atoms of each kind are present in a chemical compound. Look at the structure of a water molecule. Each water molecule contains 2 hydrogen atoms and 1 oxygen atom. A subscript of ‘1’ is never written in formulas. Look at the formulas on the right and identify the error in each. H2O1H2O1 H2OH2O (H) 2 O OH 2  / / / 3

4. 1A 1 H (2.1) hydrogen 1 -1 2A 3A4A5A6A7A 3 Li (1.0) lithium 1 --- 4 Be(1.5) beryllium 2 --- 5 B (2.0) boron 3 --- 6 C (2.5) carbon 2, 4 -4 7 N (3.0) nitrogen 2,3,4,5 -3 8 O (3.5) oxygen --- -2 9 F (4.0) fluorine --- -1 11 Na (1.0) sodium 1 --- 12 Mg (1.2) magnesium 2 --- 13 Al (1.5) aluminum +3 --- 14 Si (1.8) silicon 4 --- 15 P (2.1) phosphorus 3, 4, 5 -3 16 S (2.5) sulfur 2, 4, 6 -2 17 Cl (3.0) chlorine 1,3,5,7 19 K (0.9) potassium 1 --- 20 Ca (1.0) calcium 2 --- 31 Ga (1.7) gallium 3 --- 32 Ge (1.9) germanium 4 --- 33 As (2.1) arsenic 3, 5 -3 34 Se (2.4) selenium 4, 6 -2 35 Br (2.8) bromine 1, 5 37 Rb (0.9) rubidium 1 --- 38 Sr (1.0) strontium 2 --- 49 In (1.6) indium 1, 3 --- 50 Sn (1.8) tin 2, 4 --- 51 Sb (1.9) antimony 3, 5 -3 52 Te (2.1) tellurium 4, 6 -2 53 I (2.5) iodine 1, 5, 7 55 Cs (0.8) cesium 1 --- 56 Ba (1.0) barium 2 --- 81 Tl (1.6) thallium 1, 3 --- 82 Pb (1.7) lead 2, 4 --- 83 Bi (1.8) bismuth 3, 5 --- 84 Po (1.9) polonium 2, 4 --- 85 At (2.1) astatine 87 Fr (0.8) francium 1 --- 88 Ra (1.0) radium 2 --- Electronegativity (EN) values of A-group Elements H 2 O EN:2.1 (H) < 3.5 (O) The less EN atom is listed first. Practice: Write the formula of a compound made of … one S & two Na atoms Na 2 S 1.0 (Na) < 2.5 (S) one P & three Br atoms PBr 3 2.1 (P) < 2.8 (Br) two Cl’s & one Mg atom MgCl 2 1.2 (Mg) < 3.0 (Cl) In formulas of ionic compounds, symbols of metals precede nonmetals because all metals have lower EN values than any nonmetal. 4

5. Chemical Formulas of Binary Compounds Use the table of EN values to write the chemical formulas of the compounds shown below… EN:Al (1.5) < O (3.5) Al 2 O 3 C (2.5) < O (3.5) CO 2 Ca (1.0) < F (4.0) CaF 2 5

6. Some Exceptions in Chemical Formulas of Binary Compounds The least Electronegative atom in binary compounds are usually listed first, but there are a few historical exceptions … In the formulas of hydrocarbon compounds (abbreviated HC’s), which are compounds containing only hydrogen and carbon, C (EN=2.5) is listed before H (EN=2.1), even though C has the higher EN value. Most formulas of binary compounds, in which H is listed first, are acids, such as hydrochloric acid, HCl and hydrofluoric acid, HF. HC’s are not acidic so their H’s are listed last. CH 4, methane, is the major component of natural gas. C 2 H 6, ethane is the 2 nd largest component of natural gas 6

7. More Exceptions in Chemical Formulas of Binary Compounds In the formulas of binary compounds containing nitrogen, N is usually listed first regardless of its EN value. Ammonia, NH 3, is not acidic. It’s a moderately strong base. Listing H first would make ammonia look acidic … H 3 N In ammonia, NH 3, EN N (3.0) > H (2.1), but N is written first. In N 2 O 5, N (3.0) < O (3.5) N is less EN and written first. 7 / /

8. Naming Binary Compounds There are three systems for naming binary compounds 1.The Stock System (the most comprehensive) e.g., sodium chloride 2.The Prefix System (for nonmetal compounds only) e.g., carbon monoxide, carbon dioxide 3.The ous-ic system (has limited use) e.g., ferrous oxide, ferric oxide 8

9. The Stock System for Naming Binary Compounds CaCl 2 = calcium chlorideAl 2 O 3 = aluminum oxide name of less EN atom first name of more EN atom ends in ‘ide’ a space between name of less EN atom first name of more EN atom ends in ‘ide’ a space between chlorine  chloride oxygen  oxide In ionic compounds (made of metal cations, ⊕ and nonmetal anions, ⊖ ), the less EN atom is a metal cation, and the more EN atom is a nonmetal anion. The name of the metal cation is the same as the element’s name but the anion’s name ends in ‘ide’. Note that the Stock system name does not tell us the relative number of atoms in the formula. This will be explained later. 9

10. 1A 8A 1 H (2.1) hydrogen 1 -1 2A 3A4A5A6A7A He Helium 3 Li (1.0) lithium 1 --- 4 Be(1.5) beryllium 2 --- 5 B (2.0) boron 3 --- 6 C (2.5) carbon 2, 4 -4 7 N (3.0) nitrogen 2,3,4,5 -3 8 O (3.5) oxygen --- -2 9 F (4.0) fluorine --- -1 Ne Neon 11 Na (1.0) sodium 1 --- 12 Mg (1.2) magnesium 2 --- 13 Al (1.5) aluminum +3 --- 14 Si (1.8) silicon 4 --- 15 P (2.1) phosphorus 3, 4, 5 -3 16 S (2.5) sulfur 2, 4, 6 -2 17 Cl (3.0) chlorine 1,3,5,7 Ar Argon 19 K (0.9) potassium 1 --- 20 Ca (1.0) calcium 2 --- 31 Ga (1.7) gallium 3 --- 32 Ge (1.9) germanium 4 --- 33 As (2.1) arsenic 3, 5 -3 34 Se (2.4) selenium 4, 6 -2 35 Br (2.8) bromine 1, 5 Kr Krypton 37 Rb (0.9) rubidium 1 --- 38 Sr (1.0) strontium 2 --- 49 In (1.6) indium 1, 3 --- 50 Sn (1.8) tin 2, 4 --- 51 Sb (1.9) antimony 3, 5 -3 52 Te (2.1) tellurium 4, 6 -2 53 I (2.5) iodine 1, 5, 7 Xe Xenon Learn the anion names & charges. Nonmetal anions gain enough electrons to fill their valence shell to become isoelectronic with the nearest noble gas. 10 Anions typically have only 1 possible Ox #, which is easy to learn if you know their Group number on the PD table

11. Practice naming these binary compounds using the Stock system: K 3 P MgO Al 2 S 3 Ca 3 N 2 MgF 2 LiI Be 2 C potassium phosphide magnesium oxide aluminum sulfide calcium nitride magnesium fluoride lithium iodide beryllium carbide BaBr 2 CaH 2 Na 2 Se SrCl 2 B 2 O 3 SiC HF barium bromide calcium hydride sodium selenide strontium chloride boron oxide silicon carbide hydrogen fluoride Note that the last three examples are not ionic compounds. They are composed of metalloids and/or nonmetals only, yet the Stock system names all compounds as if they were ionic. The less EN atom is first (using the atom’s name). The more EN atom is last (using the anion’s ‘ide’ name). 11

12. Writing Chemical Formulas of Binary Compounds In order to write formulas and name compounds, you will need the ‘oxidation numbers’ (Ox #’s) of the atoms/ions in a compound. Ox #’s are explained in detail in a video entitled ‘Oxidation Numbers’ and will only be discussed briefly in this lesson. What is an oxidation number (Ox #)? Ox # is a charge assigned to an atom or ion in a compound. All pure elements have an Ox # = 0, e.g., Ox # Cu=0, H 2 =0, S 8 =0. About 20 elements have only one Ox # (fixed Ox #’s), other than 0, and they must be memorized, but it is easy to do so if you learn their position on the periodic table. The Ox #’s of other atoms/ions are calculated from the chemical formula. 12

13. Fixed Ox #’s are highlighted (red and yellow). Metals cannot have ⊖ Ox #’s (they never gain e’s). Most nonmetals can have ⊖ or ⊕ Ox #’s, e.g., Cl in ICl (Cl = -1), Cl in ClF (Cl = +1), Cl in ClO 2 (Cl = +4), Cl in ClF 7 (Cl = +7). Note that the nonmetal with higher EN always gets a ⊖ Ox # 13 Fixed Ox #’s are easily memorized by knowing their A-Group number on the PD table. Other Ox #’s can all be calculated.

14. Writing the Formulas of Binary Compounds Chemical formulas represent the smallest whole number ratio of atoms/ions in a compound. The positive and negative charges (Ox #’s) must add up to zero; the charges balance. Stepscalcium chlorideboron bromidehydrogen sulfidemagnesium phosphide 4. Use subscripts to write the formulas BBr 3 H2SH2SMg 3 P 2 calcium: Ca +2 chloride: Cl - 1 Ca +2 ion for every 2 Cl - ions CaCl 2 Ca +2 = +2 Cl - -1 -1 = -2 1. Obtain ion symbols & Ox #’s (charges) 2. Find the total charge needed to balance + & - charges 3. Find the ratio of + and - ions boron: B +3 (2.0EN) bromide: Br - (2.8EN) B +3 = +3 Br - -1 -1 -1 = -3 1 B +3 ion for every 3 Br - ions hydrogen: H + (2.1EN) sulfide: S -2 (2.5EN) H +1 +1 +1 = +2 S -2 = -2 2 H + ions for every 1 S -2 ion magnesium: Mg +2 phosphide: P -3 Mg +2 +2 +2 +2 = +6 P -3 -3 -3 = -6 3 Mg +2 ions for every 2 P -3 ions Nonmetals such as Cl, Br, H, S and P can have ⊕ or ⊖ Ox #’s. An atom is assigned a ⊕ Ox # when it is the less EN atom in a compound and a ⊖ Ox # when it is the more EN atom in a compound. 14

15. Practice writing the chemical formulas of binary compounds : name ionsformula magnesium oxide potassium nitride barium fluoride silicon iodide beryllium carbide calcium hydride lithium selenide sodium phosphide zinc phosphide aluminum sulfide boron oxide Mg +2 O -2 K + N -3 Ba +2 F - Al +3 S -2 B +3 O -2 Si +4 I - Be +2 C -4 Ca +2 H - Li + Se -2 Na + P -3 Zn +2 P -3 MgO K3NK3N BaF 2 Al 2 S 3 B2O3B2O3 SiI 4 Be 2 C CaH 2 Li 2 Se Na 3 P Zn 3 P 2 A chemical formula shows the lowest whole number ratio of ions such that the total positive and negative charges are equal. The ‘Inverse rule’ is an easy way to find this ratio. Consider zinc phosphide. Zn +2 P -3  Zn 3 P 2 The number of Zn cations (3) equals the charge of the anion (-3), and the number of P anions (2) equals the charge of the cation (+2). But remember to reduce this to the lowest whole number ratio. Consider beryllium carbide. Be +2 C -4  Be 4 C 2  Be 2 C 15

16. Finding an Ox # in Compounds Containing a Multivalent Ion water = H 2 Owater ≠ HO 2 or H 3 O or HO, etc. because the Ox # H = +1 and Ox # O = -2 In order to combine elements in a chemical formula in the correct ratio, you need to know the Ox #’s of each element. You will also need to know these Ox #’s for writing chemical names. However many elements are ‘multivalent’; they have more than one possible Ox #. Fortunately, it is always true that at least one of the elements in a binary compound will have an Ox # that is known for certain and so the other element’s Ox # can be calculated. Example 1: Manganese has 5 different Ox #’s in its compounds, i.e., +2, +3, +4, +6 and +7. Calculate the Ox # of Mn in MnCl 2. Answer: Mn = +2 Here’s why: The Ox # of Cl is -1 because it is more EN than Mn. Chloride is always -1. The total negative charge in MnCl 2 = (Cl -1 × 2) = -2. So the total positive charge of Mn must be +2, and the Ox # of Mn must be +2. 16

17. Example 2: Calculate the Ox # of Mn in Mn 2 O 3 Answer: Mn = +3 Here’s why: The Ox # of O is always -2. The total negative charge of three O’s = (-2 × 3) = -6 The total positive charge of both Mn ions must be +6 (total ⊕ = total ⊖ ). So each Mn has a charge of (+6/2) = +3 or solve as a math equation: Let Ox # of Mn = x The sum of all Ox #’s = 0 Mn 2 O 3 = 0 (x)*2 + (-2)*3 = 0 2x – 6 = 0 x = + 6/2 = +3  Mn +3 or use the Inverse Rule: Mn 2 O 3 -2 +3 17

18. Practice: Calculate the Ox # of the underlined ion in each formula Formulaanion chargecation chargeFormulaanion chargecation charge MnO 2 Cu 3 P MnO 3 PbF 4 Mn 2 O 7 PCl 5 V3N5V3N5 Mo 2 S 5 Fe 4 C 3 NiH 3 -3-2 -3 -4 +4 +6 +7 +5 +3 -2 +3 +5 +4 +1 18

19. Naming Binary Compounds Containing a Multivalent Ion: Iron (Fe), like manganese (Mn) can exhibit more than one Ox #. There are two kinds of iron chloride, FeCl 2 and FeCl 3. The name ‘iron chloride’ is thus ambiguous. In binary compounds containing cations with more than one Ox #, the Ox # of the cation is written in Roman numerals (in parentheses) immediately after the cation. Thus FeCl 2 is named iron(II) chloride and FeCl 3 is named iron(III) chloride. There are two different forms of iron chloride. Iron(II) chloride is green. Iron(III) chloride is yellow/rusty colored. Each different chemical compound must have its own, unique, unambiguous name. 19

20. Look at the formulas and names of two kinds of iron oxide, FeO and Fe 2 O 3. Please read carefully: The Ox # listed immediately after the cation indicates the charge on the cation, not necessarily the number of anions in the formula. To name a compound, write the ion symbols and determine their Ox #’s from the combining ratio given in the formula. The anion usually has only one possible Ox #, so calculate the Ox # of the cation remembering that the total ⊕ charge and ⊖ charges in compounds are equal. FeO is black Fe 2 O 3 is rusty/red 20

21. Naming Binary Compounds Containing a Multivalent Ion: StepsAu 3 NCl 2 O 5 5.Write the name of the compound 1.Identify the Ox # that is known for certain (usually the anion’s). 2.If allowed, check the periodic table for the possible charges of the other ion. 3.Determine the ratio of ions in the formula 4.Find what charge must be on the multivalent ion to balance all charges chlorine(V) oxide nitride: N -3 (Group 5A) (N is more EN than Au, so it uses its negative Ox #) Au + or Au +3 Au 3 N means 3 gold ions for every 1 nitride ion. Au + +1 +1 +1 = +3 N -3 = -3 3 Au + ions are needed for every 1 N -3 ion gold(I) nitride oxide: O -2 (Group 6A) O is more EN than Cl, O always has an Ox # of -2 Cl +, Cl +3, Cl +5 or Cl +7 Cl 2 O 5 means 2 chlorines for every 5 oxide ions. Cl +5 : +5 +5 = +10 O 2- : -2 -2 -2 -2 -2 = -10 2 Cl +5 atoms are needed for every 5 O -2 ions. 21

22. name formula ions name formula ions FeOFe 2 O 3 CrO 3 MnS 2 NiF 3 CoCl 3 CuOCoO Cu 2 OSn 3 N 4 AuBr 3 Sn 3 N 2 Fe +2 O -2 Cr +6 O -2 Ni +3 F - Cu +2 O -2 Cu + O -2 Au +3 Br - Fe +3 O -2 Mn +4 S -2 Co +3 Cl - Co +2 O -2 Sn +4 N -3 Sn +2 N -3 iron(II) oxide chromium(VI) oxide nickel(III) fluoride copper(II) oxide copper(I) oxide gold(III) bromide iron(III) oxide manganese(IV) sulfide cobalt(III) chloride cobalt(II) oxide tin(IV) nitride Practice Naming Binary Compounds Containing a Multivalent Ion: Determine Ox #’s of the ions in the compounds below. Use these Ox #’s to write Stock system names of the compounds. tin(II) nitride 22

23. Practice Writing Formulas of Binary Compounds Containing Multivalent Ions: nameformulaionsnameformulaions chromium(III) oxidecobalt(III) phosphide nickel(II) fluoridevanadium(V) chloride titanium(IV) oxidetungsten(IV) carbide Cr +3 O -2 Ni +2 F - Ti +4 O -2 TiO 2 NiF 2 Cr 2 O 3 CoP VCl 5 WC Co +3 P -3 V +5 Cl - W +4 C -4 Note: The formula of a binary compounds does not show the charge of the cation or the anion. Do not write any charges in binary compound formulas. For example, sodium chloride’s formula is NaCl, not Na + Cl -. 23

24. Binary Acids: Binary acids contain hydrogen, H, that is covalently bonded to a non metal. Hydrogen chloride, HCl, is an example of a binary acid. When dissolved in water, hydrogen chloride is named hydrochloric acid because it releases an acidic H + ion when it ionizes. Learn the names and formulas of the five common binary acids, listed below. name (anhydrous) name (in water)formula reaction in water HF HCl HBr HI H2SH2S hydrogen fluoride hydrogen chloride hydrogen bromide hydrogen iodide hydrogen sulfide hydrofluoric acid hydrochloric acid hydrobromic acid hydroiodic acid hydrosulfuric acid HF  H + + F - HCl  H + + Cl - HBr  H + + Br - HI  H + + I - H 2 S  2H + + S -2 24

25. Summary of Stock System Nomenclature for Binary Compounds SnOtin(II) oxideNaClsodium chloride SnO 2 tin(IV) oxideCaCl 2 calcium chloride Cr 2 O 3 chromium(III) oxideAl 2 O 3 aluminum oxide CrO 3 chromium(VI) oxideZnSzinc sulfide CuBrcopper(I) bromideAg 3 Psilver phosphide CuBr 2 copper(II) bromide There is > 1 tin oxide, chromium oxide, copper bromide. Sn, Cr, Cu have > 1 Ox # Sn (+2, +4), Cr (+2, +3, +6), Cu (+1, +2) Ox #’s must be included in the name (written in Roman numerals). There is only one sodium chloride, calcium chloride, aluminum oxide, zinc sulfide, and silver phosphide. Na, Ca, Al, Zn, Ag have only 1 Ox # each. Na & Ag (+1), Ca & Zn (+2), Al (+3) The Ox # is not stated in the name. 25

26. The Prefix System for Binary Compounds For binary compounds containing two non-metals, a Greek or Latin prefix is attached to the name of an element to indicate the number of atoms of that element in the compound. Number 1 2 3 4 5 6 Formula CO CO 2 SO 3 CCl 4 PCl 5 SF 6 Prefix System Name carbon monoxide carbon dioxide sulfur trixode carbon tetrachloride phosphorus pentachloride sulfur hexafluoride Prefix mono di tri tetra penta hexa 7 = hepta, 8 = octa, 9 = ennea, 10 = deca Although this system is used almost exclusively for non-metal/non-metal compounds, occasionally, it is used when a metal is present. Attach a prefix to the 2 nd atom in the formula (always). Attach a prefix to the 1 st atom in the formula (only if there is more than one of them). 26

27. Name the following compounds using both the Prefix system and the Stock system : Formula N 2 O NO NO 2 N 2 O 3 N 2 O 4 N 2 O 5 ICl CS 2 SO 2 PCl 3 P 2 O 5 SCl 6 MnO 2 Prefix System Name dinitrogen monoxide nitrogen monoxide nitrogen dioxide dinitrogen trioxide dinitrogen tetr(a)oxide dinitrogen pent(a)oxide iodine monochloride carbon disulfide sulfur dioxide phosphorus trichloride diphosphorus pent(a)oxide sulfur hexachloride manganese dioxide Stock System Name nitrogen(I) oxide nitrogen(II) oxide nitrogen(IV) oxide nitrogen(III) oxide nitrogen(IV) oxide nitrogen(V) oxide iodine(I) chloride carbon(IV) sulfide sulfur(IV) oxide phosphorus(III) chloride phosphorus(V) oxide sulfur(VI) chloride manganese(IV) oxide 27

28. The “Ous-Ic” System For binary compounds in which the cation usually has only 2 oxidation states, the old “ous-ic” system is sometimes used. In a few cases, when the English name of the metal atom is awkward, the Latin name of the metal is used instead. Then the suffix “ous” is added for the lower oxidation number and “ic” for the higher oxidation number. Symbol Cu Fe Pb Sn Au Hg Pt Co Latin Name cuprum ferrum plumbum stannum aurum --- Ion Charge & Name Cu + = cuprous, Cu +2 = cupric Fe +2 = ferrous, Fe +3 = ferric Pb +2 = plumbous, Pb +4 = plumbic Sn +2 = stannous, Sn +4 = stannic Au + = aurous, Au +3 = auric Hg + = mercurous, Hg +2 = mercuric Pt +2 = platinous, Pt +4 = platinic Co +2 = cobaltous, Co +3 = cobaltic Name copper iron lead tin gold mercury platinum cobalt 28

29. Name the following compounds using the “ous-ic” system. Formula PbCl 2 PbCl 4 SnBr 2 SnBr 4 Cu 2 O CuO FeO Fe 2 O 3 Au 2 S 3 PtF 2 PtS 2 Hg 4 C Hg 3 N 2 Ous-Ic Name plumbous chloride plumbic chloride stannous bromide stannic bromide cuprous oxide cupric oxide ferrous oxide ferric oxide auric sulfide platinous fluoride platinic sulfide mercurous carbide mercuric nitride Stock System Name lead(II) chloride lead(IV) chloride tin(II) bromide tin(IV) bromide copper(I) oxide copper(II) oxide iron(II) oxide iron(III) oxide gold(III) sulfide platinum(II) fluoride platinum(IV) sulfide mercury(I) carbide mercury(II) nitride 29

30. 30 Peroxides: A reactive type of compound, called ‘peroxides’, has important commercial and industrial applications. The most familiar example is hydrogen peroxide, H 2 O 2. H 2 O hydrogen oxide H 2 O 2 hydrogen peroxide ‘per’ means one more O than the normal oxide. H 2 O 2 is one of the strongest oxidizers known. 35 – 50% aqueous solutions are used industrially for pulp and paper bleaching. Up to 12% H 2 O 2 is used as hair bleach and 3% H 2 O 2 is sold as a household disinfectant. Peroxides are unusual, in that the ‘O’ in a peroxide has an Ox # = -1 and the formula of the peroxide anion is written O 2 -2 (because the peroxide anion is a bonded pair of O’s). Recall that ‘O’ is in Group 6A, it will be stable when it gains 2 electrons and becomes oxide, O -2, so it is not surprising that peroxide, O 2 -2, is so reactive (unstable).

31. Group 1A and 2A metal peroxides have some interesting applications. For example, sodium peroxide, Na 2 O 2, converts carbon dioxide to oxygen and sodium carbonate. Na 2 O 2 + CO 2  Na 2 CO 3 + ½ O 2 Both lithium peroxide and sodium peroxide have been used to regenerate oxygen from exhaled air in confined spaces, such as submarines and spacecraft. Peroxide Practice: Write the name or formula of the following compounds. Spelling counts. Formula H2OH2O H2O2H2O2 BaO 2 K2O2K2O2 K2OK2O CaO 2 Stock System Name hydrogen oxide (Prefix name: dihydrogen monoxide) hydrogen peroxide barium peroxide potassium peroxide potassium oxide calcium peroxide Ox # & Charges H + O -2 H + O 2 -2 Ba +2 O 2 -2 K + O 2 -2 K + O -2 Ca +2 O 2 -2 31 Note that peroxide formulas, such as H 2 O 2, Na 2 O 2, etc. are not reduced to the lowest whole number ratio. Do not write HO or NaO. All peroxides contain a pair of bonded O’s. Finished Part 1.

32. 32 Congrats, you just completed inorganic chemical nomenclature part 1 on Binary Compounds There is also a second video dealing with the nomenclature of Polyatomic Compounds. Youtube ‘Inorganic Chemical Nomenclature Part 2 Polyatomic Compounds’

33. 33 Intro to Inorganic Chemical Nomenclature Part 2, Polyatomic Compounds This lesson was divided into two parts Part 2 Polyatomic Compounds In this video we will study the nomenclature of Polyatomic Compounds There is also a first video in which I presented the nomenclature of Binary Compounds. You should complete that video first. Youtube ‘Inorganic Chemical Nomenclature Part 1 Binary Compounds’

34. Inorganic Nomenclature Part 2 Polyatomic Compounds Oxy Acids: Oxyacids contain H, O and another nonmetal atom. Many oxyacids are commonly found in cleaning products, fruits, food ingredients, industrial chemicals, etc. Phosphoric acid, H 3 PO 4, is used to pickle steel and is the flavour in root beers and colas. Sulfuric acid, H 2 SO 4, is the electrolyte in the automobile lead-acid battery (35% H 2 SO 4 ). Carbonic acid, H 2 CO 3, is formed when carbon dioxide, CO 2, is dissolved in water (H 2 O + CO 2  H 2 CO 3 ). Carbonated beverages contain carbonic acid. A 5% solution of acetic acid, CH 3 COOH, in water is sold as vinegar. 34

35. Here are eight important oxyacids. Some of these exist with varying numbers of oxygen atoms. The ‘main’ oxyacids, the –ic acids, and their names are highlighted. ACarNeverStaysPerfectlyClean When oxyacids react, they release hydrogen ions, H +, and leave behind polyatomic anions. HNO 3  H + + NO 3 - andH 2 SO 4  2H + + SO 4 -2 and H 3 PO 4  3H + + PO 4 -3 ic acids per … ic … ic … ous hypo … ous Acetic CH 3 COOH Carbonic H 2 CO 3 Nitric HNO 3 HNO 2 Sulfuric H 2 SO 4 H 2 SO 3 Phosphoric H 3 PO 4 H 3 PO 3 H 3 PO 2 Chloric HClO 4 HClO 3 HClO 2 HClO Bromic HBrO 4 HBrO 3 HBrO 2 HBrO Iodic HIO 4 HIO 3 HIO 2 HIO ACarNeverStaysPerfectlyClean ate anions per … ate … ate … ite hypo … ite Acetate CH 3 COO - Carbonate CO 3 -2 Nitrate NO 3 - NO 2 - Sulfate SO 4 -2 SO 3 -2 Phosphate PO 4 -3 * HPO 3 -2 ** H 2 PO 2 - Chlorate ClO 4 - ClO 3 - ClO 2 - ClO - Bromate BrO 4 - BrO 3 - BrO 2 - BrO - Iodate IO 4 - IO 3 - IO 2 - IO - 35 * H 3 PO 3 only has 2 acidic H’s, so phosphite is HPO 3 -2 ** H 3 PO 2 only has 1 acidic H, so hypophosphite is H 2 PO 2 -

36. +1 + Practice: Study the structures and learn the formulas and names of the acids and their anions. CH 3 COOH acetic acid CH 3 COO - acetate +1 + 2 -2 H 2 CO 3 carbonic acid CO 3 -2 carbonate +1 + HNO 3 nitric acid NO 3 - nitrate +1 + 2 -2 H 2 SO 4 sulfuric acid SO 4 -2 sulfate +1 + 3 -3 H 3 PO 4 phosphoric acid PO 4 -3 phosphate +1 + HClO 3 chloric acid ClO 3 - chlorate 36

37. Practice: Study the Lewis structures and learn the formulas & names of the acids and their anions. CH 3 COOH acetic acid CH 3 COO - acetate H 2 CO 3 carbonic acid CO 3 -2 carbonate HNO 3 nitric acid NO 3 - nitrate H 2 SO 4 sulfuric acid SO 4 -2 sulfate H 3 PO 4 phosphoric acid PO 4 -3 phosphate HClO 3 chloric acid ClO 3 - chlorate 37

38. Other Polyatomic Ions: A few other important polyatomic ions are shown below. HCN hydrocyanic acid CN - cyanide H2OH2O water OH - hydroxide NH 3 ammonia NH 4 + ammonium +1 + +1 + +1 + HCN, hydrogen cyanide is acidic. In water it is called hydrocyanic acid. Although it is a weak acid and has a sweet almond odour, it is highly toxic when ingested. HCN  H + + CN - The formula of water, H 2 O, looks like other binary acids, but water is completely neutral. When a H + ion is removed from water, hydroxide ion, OH -, a strong base is formed. Ammonia, NH 3, is a moderately strong base with a pungent odour – the smell of Windex. When NH 3 reacts with H +, an ammonium cation, NH 4 +, is formed: NH 3 + H +  NH 4 + NH 4 + (ammonium ion) is the only polyatomic ion listed that is a cation. Its ‘ium’ ending indicates that it is a cation. The polyatomic anions have endings ‘ate’, ‘ite’, and ‘ide’. 38

39. Other Polyatomic Ions: A few other important polyatomic ions are shown below. HCN hydrocyanic acid CN - cyanide H2OH2O water OH - hydroxide NH 3 ammonia NH 4 + ammonium HCN, hydrogen cyanide is acidic. In water it is called hydrocyanic acid. Although it is a weak acid and has a sweet almond odour, it is highly toxic when ingested. HCN  H + + CN - The formula of water, H 2 O, looks like other binary acids, but water is completely neutral. When a H + ion is removed from water, hydroxide ion, OH -, a strong base is formed. Ammonia, NH 3, is a moderately strong base with a pungent odour – the smell of Windex. When NH 3 reacts with H +, an ammonium cation, NH 4 +, is formed: NH 3 + H +  NH 4 + NH 4 + (ammonium ion) is the only polyatomic ion listed that is a cation. Its ‘ium’ ending indicates that it is a cation. The polyatomic anions have endings ‘ate’, ‘ite’, and ‘ide’. 39

40. Monoprotic and Polyprotic Acids: Acids like CH 3 COOH, HNO 3, HNO 2, HClO 4, HClO 3, HClO 2, HClO, etc. have only one ionizable H + ion per molecule; these are called monoprotic acids. The three H’s bonded to C in CH 3 COOH are not ionizable. Acids like H 2 CO 3, H 2 SO 4, H 2 SO 3 and H 3 PO 4 can release more than one H + ion per molecule; they are called polyprotic acids because they can release more than one H + (proton). When polyprotic acids lose some but not all of their ionizable H’s, important polyatomic anions form. H 2 CO 3  H + + HCO 3 -  H + + H 2 SO 4  H + + HSO 4 -  H + + H 2 SO 3  H + + HSO 3 -  H + + H 3 PO 4  H + + H 2 PO 4 -  H + + HPO 4 -2  H + + HCO 3 - CO 3 -2 HSO 4 - SO 4 -2 HSO 3 - SO 3 -2 H 2 PO 4 - HPO 4 -2 PO 4 -3 bicarbonate or monohydrogen carbonate carbonate bisulfate or monohydrogen sulfate sulfate bisulfite or monohydrogen sulfite sulfite dihydrogen phosphate monohydrogen phosphate phosphate 40

41. The stepwise ionization of some polyprotic acids is shown. H 3 PO 4 phosphoric acid H 2 PO 4 - dihydrogen phosphate H 2 PO 4 - dihydrogen phosphate HPO 4 -2 monohydrogen phosphate HPO 4 -2 monohydrogen phosphate PO 4 -3 phosphate H 2 SO 4 sulfuric acid HSO 4 - bisulfate HSO 4 - bisulfate SO 4 -2 sulfate H 2 SO 3 sulfurous acid HSO 3 - bisulfite 41

42. Formulas and Names Involving Polyatomic Ions: Compounds containing polyatomic ions are named the same as binary compounds. Formulas containing polyatomic ions are written the same as binary compounds, with one difference … sodium chloride is NaCl calcium chloride is CaCl 2 sodium hydroxide is NaOH calcium hydroxide is Ca(OH) 2 Parentheses are not placed around monatomic ions like Cl -, even when several are present in the formula. Parentheses are placed around polyatomic ions like OH -, only when several are present in the formula. Ammonium hydroxide, NH 4 OH, contains two polyatomic ions, the ammonium cation, NH 4 +, and the hydroxide anion, OH - In ammonium cyanide, NH 4 CN, the N atom occurs twice. They remain separate so that the both the ammonium cation, NH 4 +, and the cyanide anion, CN -, are recognized. 42

43. Formula Practice: Write names or formulas in the empty cells. Use the Stock System. Zn(C 2 H 3 O 2 ) 2 Fe(C 2 H 3 O 2 ) 3 Cr(NO 2 ) 6 Mn(NO 3 ) 7 Al 2 (SO 4 ) 3 Al(HSO 4 ) 3 K 2 SO 3 Fe(HSO 3 ) 2 Ni(ClO 4 ) 2 Sn(ClO 3 ) 2 Pb(ClO 2 ) 4 HgBrO Co(BrO 3 ) 3 Cr(BrO 4 ) 3 Name zinc acetate iron(III) acetate chromium(VI) nitrite manganese(VII) nitrate aluminum sulfate aluminum bisulfate potassium sulfite iron(II) bisulfite nickel(II) perchlorate tin(II) chlorate lead(IV) chlorite mercury(I) hypobromite cobalt(III) bromate chromium(III) perbromate ions & Ox #’s Zn +2 CH 3 COO - Fe +3 CH 3 COO - Cr +6 NO 2 - Mn +7 NO 3 - Al +3 SO 4 -2 Al +3 HSO 4 - K + SO 3 -2 Fe +2 HSO 3 - Ni +2 ClO 4 - Sn +2 ClO 3 - Pb +4 ClO 2 - Hg + BrO - Co +3 BrO 3 - Cr +3 BrO 4 - 43

44. Practice: Write names or formulas in the empty cells. Use the Stock System. Formula Sr(IO 2 ) 2 (NH 4 ) 2 SO 4 LiIO Be(IO 3 ) 2 Cu(BrO 2 ) 2 Al 2 (CO 3 ) 3 Cu(HCO 3 ) 2 Ba 3 (PO 4 ) 2 Cd(IO 4 ) 2 W(CN) 6 Mo(CO 3 ) 3 V 2 (SO 3 ) 5 Pt 3 (PO 4 ) 4 Hg(HSO 4 ) 2 Name strontium iodite ammonium sulfate lithium hypoiodite beryllium iodate copper(II) bromite aluminum carbonate copper(II) bicarbonate barium phosphate cadmium periodate tungsten(VI) cyanide molybdenum(VI) carbonate vanadium(V) sulfite platinum(IV) phosphate mercury(II) bisulfate ions & Ox #’s Sr +2 IO 2 - NH 4 + SO 4 -2 Li + IO - Be +2 IO 3 - Cu +2 BrO 2 - Al +3 CO 3 -2 Cu +2 HCO 3 - Ba +2 PO 4 -3 Cd +2 IO 4 - W +6 CN - Mo +6 CO 3 -2 V +5 SO 3 -2 Pt +4 PO 4 -3 Hg +2 HSO 4 - 44

45. In most oxyacids, adding or subtracting O’s to a formula does not change the number of ionizable H’s. HNO 3 and HNO 2 are both monoprotic acids. H 2 SO 4 and H 2 SO 3 are both diprotic acids. HClO 4, HClO 3, HClO 2 and HClO are all monoprotic acids. The oxyacids of P are unique. H 3 PO 4 is triprotic, but H 3 PO 3 is only diprotic, and H 3 PO 2 is monoprotic. Examine the structures of these oxyacids and note that acidic H’s are bonded to O, not to P. 45

46. Because phosphorous acid (H 3 PO 3 ) has only two ionizable H’s, HPO 3 -2 is fully ionized and can be named monohydrogen phosphite or simply ‘phosphite’. H 3 PO 3, phosphorous acid H 2 PO 3 -, dihydrogen phosphite HPO 3 -2, monohydrogen phosphite or simply ‘phosphite’ Because hypophosphorous acid (H 3 PO 2 ) has only one ionizable H, H 2 PO 2 - is fully ionized and can be named dihydrogen hypophosphite or simply ‘hypophosphite’. H 3 PO 2, hypophosphorous acid H 2 PO 2 -, dihydrogen hypophosphite or simply ‘hypophosphite’ H 3 PO 4, phosphoric acid H 2 PO 4 -, dihydrogen phosphate HPO 4 -2, monohydrogen phosphate PO 4 -3, phosphate 46

47. As we are seeing, there are several conventions for naming the anions of partly ionized polyprotic acids. The student has latitude here, however, any correct name must identify the compound unambiguously. Try naming the following compounds using more than one correct name. Formula H 3 PO 4 NaH 2 PO 4 K 2 HPO 4 LiH 2 PO 3 Ag 2 HPO 3 NaH 2 PO 2 (NH 4 ) 2 HPO 4 (NH 4 ) 2 HPO 3 NH 4 H 2 PO 4 (NH 4 ) 2 KPO 4 Name phosphoric acid or hydrogen phosphate sodium dihydrogen phosphate or monosodium phosphate potassium monohydrogen phosphate or dipotassium phosphate lithium dihydrogen phosphite or monolithium phosphite silver monohydrogen phosphite or silver phosphite sodium dihydrogen hypophosphite or sodium hyposphosphite diammonium monohydrogen phosphate or diammonium phosphate diammonium monohydrogen phosphite or ammonium phosphite ammonium dihydrogen phosphate or monoammonium phosphate diammonium potassium phosphate ions & Ox #’s H + PO 4 -3 Na + H 2 PO 4 - K + HPO 4 -2 Li + H 2 PO 3 - Ag + HPO 3 -2 Na + H 2 PO 2 - NH 4 + HPO 4 -2 NH 4 + HPO 3 -2 NH 4 + H 2 PO 4 - NH 4 + K + PO 4 -3 47 The number of H’s need not be stated, provided the number of other cations is explicitly stated in the name. Prefixes like ‘di’ or ‘tri’ should only be used when partially ionized polyprotic acids are being named.

48. For compounds of monovalent cations (Li +, Na +, K +, NH 4 +, etc.) we have seen that there are several acceptable names … e.g., K 2 HPO 4 = dipotassium monohydrogen phosphate or potassium monohydrogen phosphate or dipotassium phosphate However, when polyvalent cations, like Ca +2, Al +3, etc. are combined with partially ionized acids, the convention is to state the number of H’s but not the number of polyvalent metal cations, as follows … Ca(H 2 PO 4 ) 2 CaHPO 4 Al(H 2 PO 4 ) 3 Al 2 (HPO 4 ) 3 Fe 2 (HPO 4 ) 3 SnHPO 4 Pb(H 2 PO 3 ) 4 Pd(H 2 PO 2 ) 4 Pd(H 2 PO 2 ) 2 calcium dihydrogen phosphate calcium monohydrogen phosphate aluminum dihydrogen phosphate aluminum monohydrogen phosphate iron(III) monohydrogen phosphate tin(II) monohydrogen phosphate lead(IV) dihydrogen phosphite palladium(IV) dihydrogen hypophosphite or palladium(IV) hypophosphite palladium(II) dihydrogen hypophosphite or palladium(II) hypophosphite Ca +2 H 2 PO 4 - Ca +2 HPO 4 -2 Al +3 H 2 PO 4 - Al +3 HPO 4 -2 Fe +3 HPO 4 -2 Sn +2 HPO 4 -2 Pb +4 H 2 PO 3 - Pd +4 H 2 PO 2 - Pd +2 H 2 PO 2 - 48

49. Practice: Write the name or formula of the following compounds. Spelling counts. The column on the right will not be marked. Formula Mg(CH 3 COO) 2 (NH 4 ) 2 SO 4 Fe 2 (CO 3 ) 3 Ba(NO 3 ) 2 Mn(ClO 2 ) 7 Cd(IO 4 ) 2 AlH 3 Be 3 N 2 Hg(BrO) 2 H ­2 SO 3 HClO 3 (NH 4 ) 2 HPO 4 Zn(H 2 PO 2 ) 2 Stock System Name magnesium acetate ammonium sulfate iron(III) carbonate barium nitrate manganese(VII) chlorite cadmium periodate aluminum hydride beryllium nitride mercury(II) hypobromite sulfurous acid chloric acid ammonium monohydrogen phosphate or diammonium phosphate zinc dihydrogen hypophosphite or zinc hypophosphite Ox # & Charges Mg +2 CH 3 COO - NH 4 + SO 4 -2 Fe +3 CO 3 -2 Ba +2 NO 3 - Mn +7 ClO 2 - Cd +2 IO 4 - Al +3 H - Be +2 N -3 Hg +2 BrO - H + SO 3 -2 H + ClO 3 - NH 4 + HPO 4 -2 Zn +2 H 2 PO 2 - 49

50. Other Common Acids: A few other inorganic acids are commonly encountered in the laboratory. Study the structures and names of these acids and their anions. Permanganic acid, HMnO 4, is monoprotic. Its potassium salt, potassium permanganate (KMnO 4 ) is a dark purple-colored reagent that is often used in the lab as a strong oxidizing titrant. Mn is in its highest oxidation state, +7, (which contributes to its strength as an oxidizer). Chromic acid, H 2 CrO 4, is a diprotic acid and strong oxidizer. Its potassium salt, potassium chromate, K 2 CrO 4, is used as an indicator for measurement of chloride by silver nitrate titration. Cr is in its highest oxidation state, +6, (which contributes to its strength as an oxidizer). Dichromic acid, H 2 Cr 2 O 7 is another strongly oxidizing diprotic acid. Its potassium salt, potassium dichromate ( K 2 Cr 2 O 7 ) is a common lab reagent. Can you calculate the Ox # of Cr in it? permanganic acid, HMnO 4 permanganate, MnO 4 - chromic acid, H 2 CrO 4 chromate, CrO 4 -2 dichromic acid, H 2 Cr 2 O 7 dichromate, Cr 2 O 7 -2 50

51. 51 Potassium permanganate, KMnO 4, is a very dark purple, crystalline solid. The permanganate ion, MnO 4 -, is released when dissolved in water, giving rise to bright purple solutions. Potassium chromate, K 2 CrO 4, is a bright yellow, crystalline solid. Aqueous solutions of this reagent are bright yellow owing to the presence of the chromate ion, CrO 4 -2. Bright orange potassium dichromate, K 2 Cr 2 O 7, when dissolved in water, releases the dichromate ion, Cr 2 O 7 -2.

52. Practice: Write the name or formula of the following compounds. Spelling counts. Formula Fe(MnO 4 ) 3 Ag 2 CrO 4 ZnCr 2 O 7 Al 2 (CrO 4 ) 3 Na 2 Cr 2 O 7 V 2 (Cr 2 O 7 ) 5 Mn 2 (SO 4 ) 7 Cr(PO 4 ) 2 Mo(MnO 4 ) 6 Cd(IO 4 ) 2 Co(BrO 3 ) 3 Ni(ClO 2 ) 2 Mg(BrO) 2 Stock System Name iron(III) permanganate silver chromate zinc dichromate aluminum chromate sodium dichromate vanadium(V) dichromate manganese(VII) sulfate chromium(VI) phosphate molybdenum(VI) permanganate cadmium periodate cobalt(III) bromate nickel(II) chlorite magnesium hypobromite Ox # & Charges Fe +3 MnO 4 - Ag + CrO 4 -2 Zn +2 Cr 2 O 7 -2 Al +3 CrO 4 -2 Na + Cr 2 O 7 -2 V +5 Cr 2 O 7 -2 Mn +7 SO 4 -2 Cr +6 PO 4 -3 Mo +6 MnO 4 - Cd +2 IO 4 - Co +3 BrO 3 - Ni +2 ClO 2 - Mg +2 BrO - 52 Almost Finished

53. Name the following compounds using the “ous-ic” system. Formula PbCl 2 PbCl 4 SnBr 2 SnBr 4 Cu 2 O CuO FeO Fe 2 O 3 Au 2 S 3 PtF 2 Pt(NO 3 ) 4 Hg(ClO 4 ) 2 Hg 2 SO 3 Ous-Ic Name plumbous chloride plumbic chloride stannous bromide stannic bromide cuprous oxide cupric oxide ferrous oxide ferric oxide auric sulfide platinous fluoride platinic nitrate mercuric perchlorate mercurous sulfite Stock System Name lead(II) chloride lead(IV) chloride tin(II) bromide tin(IV) bromide copper(I) oxide copper(II) oxide iron(II) oxide iron(III) oxide gold(III) sulfide platinum(II) fluoride platinum(IV) nitrate mercury(II) perchlorate mercury(I) sulfite 53

54. 54 Congrats, you just completed inorganic chemical nomenclature part 2 on Polyatomic Compounds There is also a previous video dealing with the nomenclature of Binary Compounds. Youtube ‘Inorganic Chemical Nomenclature Part 1 Binary Compounds’