Download Nomenclature Notes

Nomenclature Notes
Nonmetal-Nonmetal Compounds
Naming Compounds
Step 1: Look up the names of the elements on the periodic table by using the
symbols given in the formula.
Step 2: Use prefixes when naming a nonmetal-nonmetal compound. The number
following the symbol indicates the prefix to use.
*The prefixes used in compounds containing two nonmetals are:
1
mono6
hexa2
di7
hepta3
tri8
octa4
tetra9
nona5
penta10
decaStep 3: Modify the second elements’ ending to –ide.
Exception 1: Only use the prefix mono- on the second element, if there is only one
atom of the second element.
Examples: Cl2O – dichlorine monoxide
BCl2 - boron dichloride
Exception 2: If the prefix ends with an “a” or an “o” and the element starts with an
“a” or “o”, drop the “a” or “o” off the prefix.
Examples: O6 – hexoxide, NOT hexaoxide
O – monoxide, NOT monooxide
Writing Formulas
Step 1: Use the periodic table to identify the symbols of the elements (note that
the second elements’ ending is –ide meaning, for example, that bromide is actually
bromine).
Step 2: Determine what number the prefix stands for and write this number as a
subscript after the symbol. The number one (1) is not written in a formula. If no
subscript follows an element symbol, than it is understood to be a one (1).
Practice Problem Examples
“Binary Nomenclature Worksheet – Part A”
1) CO
C = carbon
O = oxygen
-no numbers follow the symbols so it’s understood that there is one of each
element
-the prefix for one is mono-the prefix for one is only used on the second element
Answer: carbon monoxide
2) CO2
C = carbon
O = oxygen
1 = mono
2 = di
Answer: carbon dioxide
“Binary Nomenclature Worksheet – Part B”
1) disilicon hexabromide
di is the prefix for “2”
hexa is the prefix for “6”
silicon is “Si”
bromide is bromine, “Br”
Answer: Si2Br6
2) chlorine dioxide
no prefix means “1”
chlorine is “Cl”
Answer: ClO2
di is the prefix for “2”
oxide is oxygen, “O”
BrassbridgeChemistry/UnitTwo/NotesNomNMNM