1. Chemical Compounds
Honors Chemistry

2. 3 Types of Formulas
Empirical: Smallest whole-number-ratio of atoms or ions in a compound
Ex. CH2 NH3
Molecular: Tells you the actual number of atoms of an element in a compound
Ex. C2H4 N2H6
Structural: Indicates how the atoms are bonded to each other

3. How does the mole relate to compounds?
REMEMBER
Atoms are too small to count or mass individually.
It is easier to count many or mass many.
amu gram
(atomic scale) (macroscopic scale)
mole
atoms, ions, molecules, or formula units
Molar Mass = mass, in grams, per 1 mole of a substance units = grams/mole (g/mol)
Example: the molar mass of H2O is
18.0 g/mol

4. % Composition = (part/whole) x 100
Molecular formulas and molar masses are used to determine Percent Composition
Definition: percentage, by mass, of each element
in a compound
% Composition = (part/whole) x 100
Problems
Calculate the % composition of NaCl
% Na:
% Cl:
39.3% Na
60.7% Cl

5. molar mass of anhydrate + x(molar mass of water)
Percent Composition of Hydrate Definition: A hydrate is an ionic compound with water embedded in it.
Calculate the % water in a hydrate, Mg3(PO4)2 . 6H2O.
molar mass of hydrate =
molar mass of anhydrate + x(molar mass of water)
% water =
370.9 g/mol Mg3(PO4)2 . 6H2O
29.1% H2O

6. How can you identify different types of compounds?
Type of Compound Identification
Ionic Begins with a metal
Covalent Begins with a nonmetal
Acid Begins with a hydrogen and is aqueous
Hydrate Ionic Compound and Water

8. Ionic Compounds Made from a positively and negatively charged ion
Overall charge of the compound is zero
Types of Ionic Compounds
Binary
Ternary

9. Binary Compounds: Composed of two monatomic ions
Primary Rules for Charges: YOU MUST KNOW THESE RULES
1 or IA +1
2 or IIA +2
3 or IIIA +3
15 or VA -3 in binary compounds with metals, H, or NH4+
16 or VIA -2 in binary compounds with metals, H, or NH4+
17 or VIIA -1 in binary compounds with metals, H, or NH4+

10. NaCl Fe2S3 iron(II) sulfide
Ionic Compounds – look at charges; roman numerals needed for elements with more than one charge (polyvalent)
a. Binary Compounds – only monatomic ions in compound
sodium chloride
iron(III) sulfide
FeS
NaCl
Fe2S3
iron(II) sulfide

11. Ionic Compounds hydrogen fluoride aluminum chloride
Binary Compounds
HF(g)
AlCl3
Cr2O3
hydrogen fluoride
aluminum chloride
chromium(III) oxide

12. Ionic Compounds
Ternary Compounds – contain 1/more polyatomic ions in compound
sodium carbonate
chromium(III) oxalate
ammonium sulfate
Na2CO3
Cr2(C2O4)3
(NH4)2SO4

13. Note for polyatomic ions:
Ionic Compounds
Ternary
Co3(AsO4)2
CuSO3
Note for polyatomic ions:
-ate vs. –ite
per- and hypo-
cobalt(II) arsenate
copper(II) sulfite

14. Ionic Compounds Mg(OH)2 CaSO4 (NH4)3PO4 magnesium hydroxide
calcium sulfate
ammonium phosphate
Mg(OH)2
CaSO4
(NH4)3PO4

15. 1 extra oxygen ClO4-1 perchlorate ClO3-1 chlorate 1 less oxygen
Anion
Description
Example
1 extra oxygen
ClO4-1
perchlorate
per_____ ate
ClO3-1
chlorate
the most common form
_______ate
1 less
oxygen
ClO chlorite
_______ ite
2 less
oxygens
ClO-1
hypochlorite
hypo_____ ite

16. Now try these… SO3-2 IO4-1 PO3-3 HSO3-1 sulfite periodate phosphite
bisulfite
SO3-2
IO4-1
PO3-3
HSO3-1

17. Check for Understanding
MgH2
magnesium hydride
calcium acetate
FeS2O3
SnI4
Ca(CH3COO)2
iron (II) thiosulfate
tin (IV) iodide

18. Molecular Compounds – formed between 2 nonmetals
*Use prefixes
mono = 1 hexa = 6
di = 2 hepta = 7
tri = 3 octa = 8
tetra = 4 nona = 9
penta = 5 deca = 10
Binary Compounds: only 2 elements in the compound; use prefixes and –ide ending
CCl4
N2O5
carbon tetrachloride
dinitrogen pentoxide

19. More Practice dihydrogen monoxide nitrogen tetrabromide S2O6 H2O NBr4
disulfur hexoxide

20. Hydrates – ionic compound with water bonded in its structure
anhydrate . xH2O
anhydrate  ionic compound
add prefix to indicate # of water molecules
CuSO4 . 5H2O
copper(II) sulfate pentahydrate

21. Acids – compounds that produce hydrogen ions in water
Mineral Acids
Binary Acids
1st word: prefix = hydro
root formed from anion
suffix –ide changed to -ic
2nd word: acid
HCl(aq)
HBr(aq)
hydrochloric acid
hydrobromic acid

22. B. Oxyacids 1st word: root from anion Suffix ate changed to ic
Suffix ite changed to ous
**Exceptions: if you have sulf or phos as roots, change the root to sulfur or phosphor
2nd word: acid
HNO3
HNO2
phosphorous acid
Nitric acid
Nitrous acid
H3PO3

23. Common Acids to Know HCl H2CO3 HClO4 H2SO4 H3PO4 HNO3
hydrochloric acid
HCl
H2CO3
HClO4
H2SO4
H3PO4
HNO3
CH3COOH = HC2H3O2
carbonic acid
perchloric acid
sulfuric acid
phosphoric acid
nitric acid
acetic acid

24. Salts
Ionic compound composed of a cation (positive ion) and an anion (negative ion) from an acid
NaCl
CaSO4
NaHCO3
NaHSO3

25. Organic Compounds >11 million compounds
Contain a C-C or C-H bond in combination with
N, O, S, P or halogens
Simplest = CH4
Most complex = DNA

26. Hydrocarbons Only have carbon and hydrogen Simplest organic compounds
From petroleum (crude oil)

28. Organic Compounds Allotropes of carbon
Allotropes: Different forms of an element in same physical state
Catenation: ability of an element to form chains and/or rings of covalently bonded atoms

29. Structural Formula
Indicates the number and types of atoms present in a molecule and also shows the bonding arrangement of the atoms
One possible isomer of C4H10
Does not show 3D shape

30. Naming Organic Compounds
Alkanes – saturated organic compound
Contains only single bonds
General Formula: CnH2n+2
Alkenes – unsaturated organic compound
Contains at least one double bond
General Formula: CnH2n
Alkynes – unsaturated organic compound
Contains at least one triple bond
General Formula: CnH2n-2
What type of organic compound is C4H10 ?

31. Naming Hydrocarbons
Find the longest chain of carbon atoms. Choose the base name that describes the number of carbon atoms in this chain. Use the following endings:
Alkane (ane), Alkene (ene), Alkyne (yne)
# C atoms
Stem 1
meth 9
non 2
eth 10
dec 3
prop 11
undec 4
but 12
dodec 5
pent 13
tridec 6
hex 14
tetradec 7
hept 15
pentadec 8
oct 16
hexadec

32. Naming hydrocarbons
Number the carbon atoms in this longest chain beginning at the end nearest the 1st branching.
If there is branching at equal distances from both ends of the longest chain, begin numbering at the end nearest the branch that is 1st in alphabetical order. 1 2 3 4

33. Naming Alkenes and Alkynes
Number the carbon atoms in the chain sequentially, beginning at the end nearer the double or triple bond. If the parent chain has more than 3 carbons, insert the number describing the position of the double or triple bond (indicated by its 1st carbon location) before the base name.
1-butene
2-butene

34. Branches/Substituents on the Main Chain
Additional Hydrocarbon branches
The hydrocarbon branches are called alkyl groups:
-CH3 methyl -CH2CH2CH propyl
-CH2CH ethyl CH2CH2CH2CH butyl
2)The organic halides are elements from group 17 in the periodic table.
The prefix can be fluoro-, chloro-, bromo- or iodo-.

35. Hydrocarbon Branches or Substituents
Assign the name (stem with yl ending) & position number to each substituent or branch. Arrange substituents in alphabetical order.
The hydrocarbon branches are called alkyl groups:
-CH3 methyl -CH2CH2CH propyl
-CH2CH ethyl CH2CH2CH2CH butyl

36. Naming hydrocarbons
Use the appropriate prefix to group like substituents: di = 2, tri = 3, tetra = 4, etc. Do not use these prefixes when alphabetizing attached groups
Write the name as a single word. Use hyphens to separate numbers & letters and commas to separate numbers. Do not leave any spaces.

37. Naming Alkenes and Alkynes
In naming alkenes and alkynes, the mulitple bond takes positional precedence over substituents on the carbon chain. The double bond is assigned the lowest possible number.
3,3-dimethyl-1-butene
4-methyl-2-pentene

38. Naming Organic Halides (Alkyl Halides)
The organic halides are named as halo- derivatives of the parent hydrocarbon. The prefix can be fluoro-, chloro-, bromo- or iodo-.
1-chloropropane
1-chloro-2-methylpropane

40. 3-ethyl-4,6-dimethyl-1-heptene
Alkene Examples
3,4-dimethyl-3-hexene
3-ethyl-4,6-dimethyl-1-heptene

41. Naming Alkynes
Named just like the alkenes except the suffix –yne is added
ethyne
1-butyne
propyne
2-butyne

42. Alkyne Examples
3-methyl-1-butyne
5-methyl-2-hexyne

43. Arrangement of Atoms
Isomers – compounds that have the same molecular formula but different structures
More C atoms in formula, more isomers
18 isomers for C8H18
35 isomers for C9H20
75 isomers for C10H22
Isomers of C6H14

44. Structural Isomers
Isomers in which the atoms are bonded together in different orders.
C4H10 (note continuous chain of C atoms)
butane methylpropane

45. Physical Properties of Structural Isomers
Melting Point (°C)
Boiling Point (°C)
Density at 20°C
Butane
-138.4
-0.5
0.5788
Methylpropane
-159.4
0.549

46. Ex #1) Butane, C4H10 Ex #2) Butene, C4H8 Ex #3) 2-Butene, C4H8
Ex #4) methyl propene, C4H8
ISOMERS

47. Functional Groups an atom or group of atoms that is responsible for the specific properties of an organic compound

48. Diffusion and Effusion
Diffusion: the mixing of molecules of 2 or more gases due to their molecular motion (spontaneous)
Effusion is the movement of gas atoms or molecules through a small opening. Gases confined in a container randomly pass through a tiny opening in the container.
ex) hole in a tire; soda bottle (CO2 escaping)

49. Graham’s Law: The rate of effusion of a gas is inversely proportional to the square root of its molar mass.
He and SF6 demo