Nomenclature. HC 2 H 3 O 2 Acetic Acid C 2 H 3 O 2. acetate ion

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1 Nomenclature C 2 H 3 O 2 - acetate ion HC 2 H 3 O 2 Acetic Acid 1

2 Forms of Chemical Bonds Most bonds are somewhere in between ionic There are 3 forms bonding atoms: Ionic complete transfer of 1 or more electrons from one atom to another (one loses, the other gains) Covalent some valence electrons shared between atoms Metallic holds atoms of a metal together and covalent. 2

3 NAMING COMPOUNDS Your ability to name compounds and write formula s hinges on your ability to recognize whether a compound is Ionic or Molecular. 3

4 COMPOUNDS FORMED FROM IONS CATION + ANION ---> COMPOUND Na + + Cl - --> NaCl A neutral compound requires equal number of + and - charges. 4

5 Naming Monatomic Ions Monatomic cations are identified simply by the element s name. Examples: K + is called the potassium cation Mg 2+ is called the magnesium cation 5

6 Naming Monatomic Ions For monatomic anions, the ending of the element s name is dropped, and the ending ide is added to the root name. Examples: F - is called the fluoride anion N 3- is called the nitride anion 6

7 Monatomic Ions 7

8 Two Types of Compounds Smallest piece Types of elements State Melting Point Ionic Formula Unit Metal and Nonmetal solid High >300ºC Molecular Molecule Nonmetals Solid, liquid or gas Low <300ºC 8

9 Naming Binary Ionic Compounds Binary ionic compounds involve combining the names of the cation and anion that makes up the compound. The name of the cation is given first, followed by the name of the anion Example: Aluminum Oxide Al 2 O 3 Name of cation Aluminum Name of anion Oxide 9

10 Naming Binary Ionic Compounds Examples: NaCl sodium chloride ZnI 2 zinc iodide Al 2 O 3 aluminum oxide 10

11 Learning Check Complete the names of the following binary compounds: Na 3 N sodium nitride KBr Al 2 O 3 MgS bromide potassium oxide aluminum Magnesium sulfide 11

12 Writing the formulas of Binary Ionic Compounds 1. Find the charge for each atom. (Remember: if you don t see a number, then it is implied to be a 1) 2. Switch the numbers on the elements.(you want to balance the positive charges and the negative charges.) Mg 2+ Cl - Mg 2+ Cl - 12

13 Writing the formulas of Binary Ionic Compounds 3. Write your formula. (Remember + and - signs Go away.) Mg 2+ Cl - MgCl 2 There is one catch! If the charges have the same magnitude, then the ions will form a compound with a 1:1 ratio. Mg +2 O 2- MgO 13

14 Learning Check Write the correct formula for the compounds containing the following ions: 1. Na +, S 2- a) NaS b) Na 2 S c) NaS 2 2. Al 3+, Cl - a) AlCl 3 b) AlCl c) Al 3 Cl 3. Mg 2+, N 3- a) MgN b) Mg 2 N 3 c) Mg 3 N 2 14

15 Stock system of Nomenclature I II III IV V VI VII VIII IX X Transition metals (the d-block elements) can form two or more cations with different charges. These elements REQUIRE Roman Numerals because they can have more than one possible charge: anything except Group 1A, 2A, Ag, Zn, Cd, and Al Examples: Fe 2+ Iron (II) Fe 3+ Iron (III) 15

16 Learning Check Complete the names of the following binary compounds with variable metal ions: FeBr 2 CuCl SnO 2 Fe 2 O 3 Hg 2 S iron ( ) bromide copper ( ) chloride Tin II I oxide ( IV ) Iron (III) oxide Mercury (I) sulfide 16

17 Polyatomic Ions NO 3 - nitrate ion NO 2 - nitrite ion 17

18 Naming Oxyanions Oxyanion: polyatomic ions that contains oxygen. Some elements can combine with oxygen to form more than one type of oxyanion. Example: nitrogen can form NO 3- or NO 2-. The name of the ion with the greater number of oxygen atoms ends in ate. The name of the ion with the smaller number of oxygen atoms ends in ite. NO 3 - NO 2 - Nitrate Nitrite 18

19 Naming Oxyanions In this example, an anion that has one fewer oxygen atom than the ite anion has is given the prefix hypo-. An anion that has one more oxygen atom that the ate anion has is given the prefix per-. ClO - ClO 2 - ClO 3 - ClO 4 - hypochlorite chlorite chlorate perchlorate 19

20 Ternary Ionic Nomenclature (Polyatomic Ions) Ionic compounds involving polyatomic ions are named in the same way as binary compounds. The name of the cation is given first followed by the name of the anion Example Al 2 (SO 4 ) 3 NH 4 Cl Aluminum sulfate Ammonium chloride 20

21 Learning Check Na 2 CO 3 MgSO 3 MgSO 4 NH 4 NO 3 CaCO 3 Ca 3 (PO 4 ) 2 sodium carbonate magnesium sulfite magnesium sulfate ammonium nitrate calcium carbonate calcium phosphate 21

22 Ternary Ionic Nomenclature Writing Formulas 1. Find the charge for each ion. (Remember: if you don t see a number, then it is implied to be a 1. It helps to circle the polyatomic ions) 2. Switch the numbers on The ions.(you want to balance the positive charges and the negative charges.) K + SO 4 2- K + SO

23 Ternary Ionic Nomenclature 3. Write your formula. Writing Formulas (Remember + and - signs Go away.) K + SO 4 2- K 2 SO 4 There is one catch! If you need more than one of the polyatomic ions to make the charge neutral, you must enclose it in parenthesis. Ca +2 CH 3 COO - Ca(CH 3 COO) 2 23

24 Ternary Ionic Nomenclature Sodium Sulfate Na + and SO 4-2 Na 2 SO 4 Iron (III) hydroxide Fe +3 and OH - Fe(OH) 3 Ammonium carbonate NH 4+ and CO 3 2 (NH 4 ) 2 CO 3 24

25 Learning Check 1. aluminum nitrate a) AlNO 3 b) Al(NO) 3 c) Al(NO 3 ) 3 2. copper(ii) nitrate a) CuNO 3 b) Cu(NO 3 ) 2 c) Cu 2 (NO 3 ) 3. Iron (III) hydroxide a) FeOH b) Fe 3 OH c) Fe(OH) 3 4. Tin(IV) hydroxide a) Sn(OH) 4 b) Sn(OH) 2 c) Sn 4 (OH) 25

26 Name the following: Mixed Practice! 1. Na 2 O 2. CaCO 3 3. PbS 2 4. Sn 3 N 2 5. Cu 3 PO 4 6. HgF 2 Sodium oxide Calcium carbonate Lead (IV) sulfide Tin (II) nitride Copper (I) phosphate Mercury (II) fluoride 26

27 Naming Molecular Compounds CO 2 Carbon dioxide All are formed from two or more nonmetals. CH 4 methane BCl 3 boron trichloride 27

28 Molecular (Covalent) Nomenclature 1. Less electronegative atom comes first. It is given a prefix only if it contributes more than one atom to the molecule. In general, the order of nonmetals in molecular names and formulas (which one comes first): C, P, N, H, S, I, Br, Cl, O, F 28

29 Molecular (Covalent)Nomenclature 2. The second element is named by combining: a prefix indicating the number of atoms contributed by the element. The root word of the second element. The ending changes to ide. 29

30 Molecular (Covalent)Nomenclature 3. The o or a at the end of a prefix is dropped if the main word starts with a vowel. P 4 O 10 tetraphosphorus decoxide NOTE: You must know the name of NH 3 It is ammonia. 30

31 Molecular Nomenclature Prefixes PREFIX monoditritetrapentahexaheptaoctanonadeca- NUMBER

32 Learning Check CO CO 2 PCl 3 CCl 4 N 2 O carbon oxide mon carbon dioxide phosphorus chloride tri carbon chloride tetra nitrogen di oxide mon 32

33 Learning Check 1. P 2 O 5 a) phosphorus oxide b) phosphorus pentoxide c) diphosphorus pentoxide 2. Cl 2 O 7 a) dichlorine heptoxide b) dichlorine oxide c) chlorine heptoxide 3. NF 3 a) nitrogen trifluoride b) mononitrogen fluoride c) nitrogen difluoride 33

34 Acid Nomenclature Acid: usually refers to a solution in water of an acid compound rather than the acid itself. Formulas usually begin with H. In binary acids, there are only two elements that make up the molecule. Example HF, hydrofluoric acid In ternary acids, ALL are aqueous and are made up of at least one polyatomic ion. Example :H 2 SO 4 sulfuric acid 34

35 Acid Nomenclature Anion Ending Acid Name No Oxygen -ide hydro-(stem)-ic acid w/oxygen -ate -ite (stem)-ic acid (stem)-ous acid An easy way to remember which goes with which for those that contain oxygen In the cafeteria, you ATE something ICky 35

36 Learning Check HBr (aq) No oxygen, -ide hydrobromic acid H 2 CO 3 Has oxygen, -ate carbonic acid H 2 SO 3 Has oxygen, -ite sulfurous acid 36

37 Learning Check hydrofluoric acid 2 elements H + F- HF (aq) sulfuric acid 3 elements, -ic nitrous acid 3 elements, -ous H + SO 4 2- H + NO 2 - H 2 SO 4 HNO 2 37

38 The End 38