1. Naming Covalent Compounds

2. To name a covalent compound, same as ionic naming except you use prefixes to represent how many atoms of each element you have
1 = mono
2 = di
3 = tri
4 = tetra
5 = penta
6 = hexa
7 = hepta
8 = octa
9 = nona
10 = deca

3. Naming Molecular Compounds
write the name of the element that is the least electronegative first.
Example: SO2
sulfur

4. 2. Write the name of the second element and change the ending to “ide” Example: SO2 sulfur oxide

5. 3. Add a prefix to the beginning of each element’s name to indicate how many of atoms of each there are (exception: you do not write the word mono in front of the first element if there is only one). Example: SO2 sulfur dioxide

6. Example: CO Carbon Carbon oxide Carbon monooxide
If the vowel combination o-o or a-o appear next to each other in the name, the first of the pair is omitted
Example: CO
Carbon
Carbon oxide
Carbon monooxide
 carbon monoxide

7. Practice Problem 1
Name the following molecular compound: CCl4

8. Practice Problem 2:
Name the following molecular compound: N2O4

9. Exceptions to the naming rule:
Hydrocarbons/Organic compounds/Alkanes
Compounds made only of carbon and hydrogen and single bonds
CH4 = methane
C2H6 = ethane
C3H8 = propane
C4H10 = butane
C5H12 = pentane
C6H14 = hexane
C7H16 = heptane
C8H18 = octane
C9H20 = nonane
C10H22 = decane

10. If contains double bond
alkenes
Change ending to –ene
ethane ethene
If contains triple bond
alkynes
change ending to –yne
Propane  propyne

11. Exceptions to the naming rule:
Common Names
H2O = water
NH3 = ammonia

12. Writing Molecular Formulas
Name tells you the elements present and the number of each atom to write as subscripts.
Example: nitrogen trifluoride

13. Practice Problem 3:
Write the molecular formula for tetraphosphorus decoxide.

14. Practice Problem 4:
Write the molecular formula for dinitrogen monoxide.