1. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 1 An ionic compound is composed of cations and anions. Ions are arranged in a repeating three-dimensional pattern, forming a crystal. The formula of an ionic compound gives the smallest possible integer number of ions in the substance (without writing charges) so that the combination is electrically neutral. The formula gives the formula unit of the compounds. A formula unit is not a molecule!

2. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 2 What is formula of the ionic compound of Mg 2+ and N 3- ? The common multiple of the charges is 6, so we need three Mg 2+ and two N 3-. The resulting formula is Mg 3 N 2

3. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 3 What is the formula of the ionic compound of Ca 2+ and PO 4 3- ? The common multiple of the charges is 6, so we need three Ca 2+ and two PO 4 3-. The resulting formula is Ca 3 (PO 4 ) 2

4. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 4 Organic Compounds An important class of molecular substances; they contain carbon combined with other elements – notably hydrogen, oxygen, and nitrogen. Hydrocarbons contain only carbon and hydrogen.

5. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 5 A functional group is a reactive portion of a molecule that undergoes predictable reactions. ExamplesName of Group Functional Group Methyl alcoholAlcohol Dimethyl etherEther Acetic acidCarboxylic acid

6. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 6 Chemical nomenclature is the systematic naming of chemical compounds. Compounds that are not organic are called inorganic compounds. Carbon monoxide, carbon dioxide, carbonates, and cyanides are also classified as inorganic compounds.

7. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 7 Naming Inorganic Compounds 1.Name the cation. 2.Name the anion.

8. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 8 Monatomic ions Ions formed from a single atom. Common monatomic ions are listed on the next slide by group and by period.

9. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 9 Common Monatomic Ions of the Main-Group Elements Bi 3+ Pb 2+ Tl 3+, Tl + Ba 2+ Cs + I-I- Te 2- Sn 2+ In 3+ Sr 2+ Rb + Br - Se 2- Ga 3+ Ca 2+ K+K+ Cl - S 2- Al 3+ Mg 2+ Na + F-F- O 2- N 3- Be 2+ Li + H-H- 6 5 4 3 2 1 VIIAVIAVAIVAIIIAIIAIA Period

10. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 10 Rules for Predicting the Charge on a Monatomic Ion 1.Most main-group metals have one monatomic ions with a charge equal to the group number. Al, in Group IIIA(3), has one ion, Al 3+. Sr, in Group IIA(2), has one ion, Sr 2+. K, in Group IA(1), has one ion, K +.

11. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 11 2.Some main-group metals with high atomic number have more than one cation. One cation will have the charge of the group number minus 2; the second cation will have a charge equal to the group number Pb in Group IVA(14) has two ions: Pb 2+ and Pb 4+ Tl in Group IIIA(13) has two ions: Tl + and Tl 3+

12. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 12 3.Most transition metals form more than one cation, of which one is +2. Zn and Cd form only the +2 ion. Ag forms only the +1 ion. 4.Nonmetal main-group elements form one monatomic anion with a charge equal to the group number minus 8. F in Group VIIA(17) forms the F - ion. S in Group VIA(16) forms the S 2- ion. N in Group VA(15) forms the N 3- ion.

13. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 13 Naming Monatomic Ions Monatomic cations are named after the element if the element forms only one cation.

14. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 14 If more than one cation forms: a.In the Stock system, the charge is written using a Roman numeral and is enclosed in parentheses. Cu 2+ is copper(II). Cu + is copper(I). b.In an older system, the suffic –ic (for the higher- charged cation) or –ous for the lower-charged cation) is added to the element’s stem. Cu 2+ is cupric. Cu + is cuprous.

15. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 15 Fe 3+ is iron(III) or ferric ion. Fe 2+ is iron(II) or ferrous ion. Hg 2+ is mercury(II) or mercuric ion. The second ion mercury forms is diatomic: Hg 2 2+ is mercury(I) or mercurous ion.

16. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 16 Cr 3+ is chromium(III) or chromic ion. Cr 2+ is chromium(II) or chromous ion. Mn 2+ is manganese(II) or manganous ion. Co 2+ is cobalt(II) or cobaltous ion. Zinc forms only Zn 2+, so it is called zinc ion. Cadmium forms only Cd 2+, so it is called cadmium ion. Silver forms only Ag +, so it is called silver ion.

17. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 17 Polyatomic Ion An ion consisting of two or more atoms chemically bonded together and carrying an electrical charge. Table 2.5 lists common polyatomic ions.

19. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 19 What are the names of the following ionic compounds? –B–BaO –C–Cr 2 (SO 4 ) 3 BaO is barium oxide. Cr 2 (SO 4 ) 3 is chromium(III) sulfate or chromic sulfate.

20. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 20 What are the chemical formulas for the following ionic compounds? –p–potassium carbonate –m–manganese(II) sulfate The ions K + and CO 3 2- form K 2 CO 3 The ions Mn 2+ and SO 4 2- form MnSO 4

21. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 21 Binary Molecular Compounds A compound composed of only two elements. Binary compound of a metal and a nonmetal are generally named using ionic rules.

22. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 22 Naming Binary Molecular Compounds We usually name the elements in the order given in the formula. Name the first element using the element name. Name the second element using the element root + -ide suffix.

23. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 23 Add a prefix to each name to indicate the number of atoms of that element. The prefix mono- is used only when needed to distinguish two compounds of the same two elements. The final vowel of the prefix is often dropped when followed by an element name that begins with a vowel. Oxygen is the most common example. N 2 O 4 dinitrogen tetroxide (“a” is dropped) NO nitrogen monoxide(only one “o”) (also called nitric oxide)

24. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 24 Prefixes (Greek) One (1)mono- Two (2)di- Three (3)tri- Four (4)tetra- Five (5)penta- Six (6)hexa- Seven (7)hepta- Eight (8)octa- Nine (9)nona- Ten (10)deca-

25. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 25 Some compounds have common names that differ from their systematic names: H 2 Shydrogen sulfide (the “di” is omitted) H 2 Owater NH 3 ammonia Common names need to be memorized.

26. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 26 Acids and Corresponding Anions Oxoacids contain hydrogen, oxygen, and a third central atom. To name an acid from its anion name: 1.Change an –ate suffix to –ic. 2.Change an –ite suffix to –ous. 3.Add the word “acid.”” For example: HNO 3 nitric acid H 2 SO 4 sulfuric acid

27. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 27 sulfuric acidH 2 SO 4 sulfate ionSO 4 2- sulfurous acid H 2 SO 3 sulfite ionSO 3 2- phosphoric acid H 3 PO 4 phosphate ionPO 4 3- nitric acidHNO 3 nitrate ionNO 3 - nitrous acidHNO 2 nitrite ionNO 2 - carbonic acid H 2 CO 3 carbonate ion CO 3 2- OxoacidOxoanion

28. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 28 hypochlorous acid HClOhypochlorite ion ClO - chlorous acid HClO 2 chlorite ion ClO 2 - chloric acid HClO 3 chlorate ion ClO 3 - perchloric acid HClO 4 perchlorate ion ClO 4 - Oxoacid Oxoanion

29. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 29 What are the names of the following compounds? –O–OF 2 –S–S 4 N 4 –B–BCl 3 OF 2 is oxygen difluoride S 4 N 4 is tetrasulfur tetranitride BCl 3 is boron trichloride

30. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 30 What are the formulas for the following binary molecular compounds? –c–carbon disulfide –n–nitrogen tribromide –d–dinitrogen tetrafluoride The formula for carbon disulfide is CS 2. The formula for dinitrogen tetrafluoride is N 2 F 4. The formula for nitrogen tribromide is NBr 3.

31. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 31 Bromine has an oxoacid, HBrO 2, bromous acid (compare to HClO 2, chlorous acid). What are the name and formula of the corresponding anion? The anion corresponding to HBrO 2 is bromite, BrO 2 -.

32. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 32 Hydrate A compound that contains water molecules weakly bound in the crystals. The formula of a hydrate is written with a dot before the water molecule(s) included. For example: CuSO 4  5H 2 O

33. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 33 Hydrates are named using the anhydrous (without water) compound name followed by the prefix for the number of water molecules included and the word “hydrate.” For example: CuSO 4  5H 2 O is named copper(II) sulfate pentahydrate.

34. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 34 A compound whose common name is green vitriol has the chemical formula FeSO 4  7H 2 O. What is the chemical name of this compound? FeSO 4  7H 2 O is iron(II) sulfate heptahydrate.

35. Copyright © Houghton Mifflin Company. All rights reserved. 2 | 35 Calcium chloride hexahydrate is used to melt snow on roads. What is the chemical formula of the compound? The chemical formula for calcium chloride hexahydrate is CaCl 2  6H 2 O.