Covalent (Molecular) Covalent (Molecular) CompoundsCompounds

*A covalent bond is a chemical bond in which two or more electrons are shared by two atoms.

All are formed from two or more nonmetals.

Properties of Covalent Properties of Covalent (Molecular) Compounds(Molecular) Compounds

Usually gases or liquids (made of molecules)

Low melting and boiling points.

Poor electrical conductors in all phases.

Many soluble in non-polar liquids but not in water.

Naming Molecular Naming Molecular CompoundsCompounds

CH4 methaneBCl3 boron trichloride

CO2 Carbon dioxide

Methane CH4

Molecular (Covalent) NomenclatureMolecular (Covalent) Nomenclaturefor two for two nonnonmetalsmetals

• Prefix System (binary compounds)

1. Less electronegative atom comes first.

2. Add prefixes to indicate # of atoms. Omit mono- prefix on the FIRST element.

3. Change the ending of the second element to -ide.

PREFIXmono-di-tri-tetra-penta-hexa-hepta-octa-nona-deca-

NUMBER123456789

10

Molecular Nomenclature PrefixesMolecular Nomenclature Prefixes

• CCl4

• N2O

• SF6

• carbon tetrachloride

• dinitrogen monoxide

• sulfur hexafluoride

Molecular Nomenclature: ExamplesMolecular Nomenclature: Examples

• arsenic trichloride

• dinitrogen pentoxide

• tetraphosphorus decoxide

• AsCl3

• N2O5

• P4O10

More Molecular ExamplesMore Molecular Examples

Learning Check Learning Check

Fill in the blanks to complete the following names of covalent compounds.

CO carbon ______oxide

CO2 carbon _______________

PCl3 phosphorus _______chloride

CCl4 carbon ________chloride

N2O _____nitrogen _____oxide

Learning Check Learning Check

1. P2O5 a) phosphorus oxide

b) phosphorus pentoxide

c) diphosphorus pentoxide

2. Cl2O7 a) dichlorine heptoxide

b) dichlorine oxide

c) chlorine heptoxide

3. Cl2 a) chlorine

b) dichlorine

c) dichloride

Mixed Review Mixed Review

Name the following compounds:

1. CaOa) calcium oxide b) calcium(I) oxidec) calcium (II) oxide

2. SnCl4

a) tin tetrachloride b) tin(II) chloride

c) tin(IV) chloride

3. N2O3

a) nitrogen oxide b) dinitrogen trioxidec) nitrogen trioxide

Solution Solution

Name the following compounds:

1. CaO

2. SnCl4

3. N2O3

a) calcium oxide

c) tin(IV) chloride

b) Dinitrogen trioxide

Mixed PracticeMixed Practice

1. Dinitrogen monoxide

2. Potassium sulfide

3. Copper (II) nitrate

4. Dichlorine heptoxide

5. Chromium (III) sulfate

6. Iron (III) sulfite

7. Calcium oxide

8. Barium carbonate

9. Iodine monochloride

Mixed PracticeMixed Practice

1.1. BaIBaI22

2.2. PP44SS33

3.3. Ca(OH)Ca(OH)22

4.4. FeCOFeCO33

5.5. NaNa22CrCr22OO77

6.6. II22OO55

7.7. Cu(ClOCu(ClO44))22

8.8. CSCS22

9.9. BB22ClCl44

Now it’s Study TimeNow it’s Study Time

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