Name____________________________
Date_____________Section_________
Naming Covalent (molecular) Compounds #1
Covalent compounds are named differently than ionic compounds. The main difference is that
covalent compounds use prefixes (mono, di, tri, etc) to tell us how many atoms of each element
are present in the compound. Otherwise, some of the rules are identical to naming ionic
compounds. Here are some of the rules. PREFIXES AND NAMING RULES CAN BE
FOUND ON PAGES 246-247 IN YOUR TEXTBOOK.
EXAMPLE:
CO
1. The element with the lowest electronegativity is written first (in the example it is carbon)
2. The name of the second element ending is changed to -ide. (example oxygen oxide)
3. Prefixes are used to tell how many atoms of each element are present. mono = one
Example Name: carbon monoxide
4. If the first element only has one atom, the prefix -mono is not used
Therefore it is NOT monocarbon monoxide but carbon monoxide
5. Some other examples
carbon dioxide = CO2
H2O = dihydrogen monoxide
ASSIGNMENT-On a sheet of loose-leaf paper complete the following.
A. From the formula (H2O for example) name the following compounds.
1. NO
2. NO2
3. N2O3
4. PH3
5. SF6
6. CCl4
7. IF7
8. B2Si
B. From the covalent compound name write the formula for the following.
1. hexaboron silicide
2. chlorine dioxide
3. hydrogen chloride
4. hydrogen iodide
5. iodine pentafluoride
6. dinitrogen trioxide
7. ammonia (look up in text)
8. phosphorus triiodide
**On Friday 11/13/09 binders will be collected for 10-1 and 10-2!!!!!
**On Monday 11/16/09 binders will be collected for 10-3 and 10-4 !!!!!!
Make sure you follow the guidelines in the grading handout in your binders and INCLUDE your
2002 Chemistry Reference Tables!!!!!!