Post on 26-Dec-2015
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NOMENCLATUREChapter 2
H2OH2O
molecular empirical
C6H12O6 CH2O
O3 O
N2H4 NH2
Chemical Formulas• Formula Unit:
• Identifies exact number of atoms in an ionic compound
• Molecular formula: • Identifies exact number of atoms in a covalent molecule
• Empirical formula:• Shows the simplest whole number ratio of atoms in a
compound
DIATOMIC ELEMENTS
Some elements do not like to be alone…
so they bond to themselves!
7HOFBrINCl
The ionic compound NaCl
Ionic Compounds• consist of a combination of cations and anions formed from a transfer of electrons• the formula unit is always identical to the empirical formula• the sum of the charges on the cation(s) and anion(s) in
each formula unit must equal zero
NAMING BINARY IONIC COMPOUNDS
RULE 1Metal – Nonmetal
1. Write the metal (positive ion) first
2. Change the ending of the second word to -ide
Rule 1 Examples
1. KBr
2. CaBr2
3. LiF
4. Li2O
5. MgO
6. BaS
7. K3P
8. Na3N
1. Potassium Bromide2. Calcium Bromide3. Lithium Fluoride4. Lithium Oxide5. Magnesium Oxide6. Barium Sulfide7. Potassium Phosphide8. Sodium Nitride
NAMING COMPOUNDS WITH POLYATOMICS
RULE 2Polyatomic Ions
1. DO NOT CHANGE ANYTHING!
2. When you have NH4 and a single element, change the second word to -ide
Rule 2 Examples
1. Ba(SO4)
2. Ba(SO3)
3. Na2(CO3)
4. Na(HCO3)
5. (NH4)3(PO4)
6. (NH4)(OH)
1. Barium Sulfate2. Barium Sulfite3. Sodium Carbonate4. Sodium Bicarbonate5. Ammonium Phosphate6. Ammonium Hydroxide
Al2O3
2 x +3 = +6 3 x -2 = -6
Al3+ O2-
Ca Br2
1 x +2 = +2 2 x -1 = -2
Ca2+ Br-
Na2CO3
1 x +2 = +2 1 x -2 = -2
Na+ CO32-
Formula of Ionic Compounds
NAMING COMPOUNDS WITH TRANSITION METALS
RULE 3Transition Metals
1. Can have more than one type of charge
2. Write the charge number in roman numerals
Rule 3 Examples
1. Cu2O
2. CuO
3. FeCl24. FeCl35. SnCl46. Mn2O3
7. PbS
1. Copper (I) Oxide2. Copper (II) Oxide3. Iron (II) Chloride4. Iron (III) Chloride5. Tin (IV) Chloride6. Manganese (III) Oxide7. Lead (II) Sulfide
NAMING HYDRATES
• What is a hydrate?
• Hydrates are named:
Compound • Prefix-Hydrate
FeCl3 • 6H2O = Iron (III) Chloride Hexahydrate
Name to Formula – Criss Cross Rule
1. Lithium Fluoride
2. Sodium Sulfide
3. Aluminum Bromide
4. Iron (III) Oxide
5. Carbonic Acid
6. Calcium Carbonate
7. Magnesium Acetate
8. Copper (II) Sulfate Pentahydrate
9. Ammonium Sulfite
10. Barium Hypochlorite
Covalent Compounds
• Referred to as molecules• Consists of nonmetals covalently bonded
• nonmetals or nonmetals + metalloids• Least electronegative element is usually written first
NAMING COVALENT COMPOUNDS
RULE 4Nonmetal – Nonmetal
USE PREFIXES!
1. Change the ending of the second word to -ide
2. No mono on the first word
3. Drop any double vowels
NO2 nitrogen dioxide
N2O dinitrogen monoxide
TOXIC!
Laughing Gas
PrefixesNumber of Atoms Prefixes
1
2
3
4
5
6
7
8
9
10
Rule 4 Examples1. CO
2. CO2
3. SO2
4. SO3
5. N2H4
6. N2O3
7. PCl38. SiO2
9. P2O5
10. CS2
11. Al2O3
1. Carbon Monoxide2. Carbon Dioxide3. Sulfur Dioxide4. Sulfur Trioxide5. Dinitrogen Tetrahydride6. Dinitrogen Trioxide7. Phosphorus Trichloride8. Silicon Dioxide9. Diphosphorus Pentoxide10. Carbon Disulfide11. Aluminum Oxide
ACIDS• a substance that yields hydrogen ions (H+) when dissolved in water.
• example: hydrochloric acid refers to a water solution of the molecular compound hydrogen chloride, HCl
• Many polyatomic ions are produced by the loss of hydrogen ions from oxyacids.
Acid Name: Polyatomic Ion: 24SO
3NO
34PO
sulfuric acid H2SO4 sulfatenitric acid HNO3 nitratephosphoric acid H3PO4 phosphate
NAMING ACIDS
• Binary acids: consist of two elements, usually hydrogen and a halogen
• “HX”
• Oxyacids: contain hydrogen and a polyatomic ion (usually oxygen and a third nonmetallic element)
• “HXO”
NaOH sodium hydroxide
KOH potassium hydroxide
Ba(OH)2 barium hydroxide
NAMING BASES
• Base: a substance that yields hydroxide ions (OH-) when dissolved in water.