Formula Assignment #5
Compound Names and Formulas
Compounds that use the
Prefix System
Prefixes and their meanings
mono = 1, di or bi = 2, tri = 3,
teta = 4,
penta = 5,
hexa = 6, hepta = 7, octo = 8, nona = 9, deca = 10
A. Write the correct
chemical formula for these compounds.
The prefix in front of the element indicates how many of that atom will
be in the compound. DO NOT USE THE CROSS
RULE FOR THESE COMPOUNDS.
1. carbon monoxide
_______________ 11. boron trichloride ________________
2. carbon
tetrachloride _____________ 12. carbon tetraiodide
_______________
3. carbon dioxide _________________ 13. boron trichloride_________________
4. sulphur
dioxide _________________ 14. carbon tetrafluoride
_______________
5. sulphur trioxide
__________________ 15. aluminum tribromide _______________
6. diphosphorous
trioxide _______________ 16.
selenium trioxide _________________
7. carbon tetrafluoride
_________________ 17. nitrogen trifluoride
_______________
8. lead dioxide
______________________ 18. sulphur
dichloride _______________
9. dihydrogen
dioxide ________________ 19. nitrogen
dioxide _________________
10. selenium
trioxide _________________ 20. dinitrogen
tetroxide
_______________
B. The following elements exist in nature as
diatomic molecules (2 atoms per molecule).
Write the formula for each of these elements.
1. hydrogen gas _____H2__________ 5. fluorine gas _________________
2. chlorine gas ________________ 6. bromine gas
________________
3. nitrogen gas ________________ 7. iodine solid
_________________
4. oxygen
gas _________________