Chapter 7-3Naming Compounds

Naming Chemical Compounds

• Compounds are named for the atoms and bonds that compose it

Prefixes

• Mono = 1• Di = 2• Tri = 3• Tetra = 4• Penta = 5

• Hexa = 6• Hepta = 7• Octa = 8• Nona = 9• Deca = 10

Ionic Compounds

• Cation first• Anion + ideOr the polyatomic anion

Name these:FeCl2

CuNO3

Ionic Compounds

• Cation first• Anion + ideOr the polyatomic anion

Name these:FeCl2 = Iron (II) chloride

CuNO3 = Copper (I) Nitrate

Ionic Compounds

• Careful with transition metals that can form ions with different charges

• Make sure your compound has a net charge of “0” neutral

• Use the crisscross method to determine the right formula

Name these:

• 1.) KNO3

• 2.) NH4Br

• 3.) Ca(OH)2

• 4.) CuSO4

• 5.) Cu2O

• 6.) Al2S3

Name these:

• 1.) KNO3 Potassium Nitrate

• 2.) NH4Br Ammonium bromide

• 3.) Ca(OH)2 Calcium hydroxide

• 4.) CuSO4 Copper (II) Sulfate

• 5.) Cu2O Copper Oxide

• 6.) Al2S3 Aluminum sulfide

Hydrates

• Hydrates: ionic substances that absorb water into their solid structure.

• Anhydrous Substances: Water free substance.

• Anhydrous copper (II) sulfate is white, but when it absorbs water it becomes blue

Hydrates • When copper (II) sulfate

fully absorbs water, it needs 5 molecules of water for each molecule of copper sulfate

• CuSO4 · 5H2O• Copper (II) Sulfate

Pentahydrate• The dot separates the

water molecules from the rest of the compound

Molecular Compounds

• Use the same prefixes for the number of atoms

• Rules are similar to ionic compounds such as using the –ide ending for the second atom

• CCl4 = Carbon tetrachloride

Molecular Compounds

• The more electronegative element usually goes last in both the written formula and the name

• Usually the prefix mono is not used when it applies to the first element

• We do not say monocarbon dioxide

Molecular Compounds

• Sometime we shorten the prefixes to make things easier to pronounce

• Carbon monoxide instead of carbon mono oxide

Molecular Compounds

• Some compounds have common names that are often used in place of their formal name

• O2 = Oxygen

• 03 = Ozone

• H2O = Water

• NH3 = ammonia

Acids

• An acid dissolves in water to release H+ ions

• They separate into cations and anions

• HCL dissolves to form H+ and Cl- ions

Acids

• Since H+ is always released, acids are named for the anion produced when dissolved

• Use the anion’s name changing the ending –ide to -ic

• Add the prefix hydro-• HF is called __________• HI is called __________

Acids

• Since H+ is always released, acids are named for the anion produced when dissolved

• Use the anion’s name changing the ending –ide to -ic

• Add the prefix hydro-• HF is called = Hydrofluoric

Acid• HI is called = Hydroiodic Acid

Acids

• Other acids are named without the prefix hydro-

• HNO3 = Nitric Acid from the anion “Nitrate”

• More examples are on page 249

Questions

• Answer Questions 1-3 on page 249

• Homework Vocabulary words page 251

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