Chapter 3 Section 3.5
Guideline #2 Tasks #3 & #4 Study Guide
†††††††††††† ††††††††Binary Molecular Compounds
Binary Molecular compounds are explained in Chapter 3 Section 3.5 Guideline #2.
1. Both elements are nonmetals attached by covalent bonds. These bonds may be single, double, or triple covalent (explained in Chapter 6)
2. Due to the covalent bonding there are many ratios of the same two elements making many different compounds. For this reason, the chemist states how many atoms of each element are present in the chemical formula in the formal name of the compound.
3. Prefixes are attached to each element to indicate how many atoms are present in the formula
4. The elementís name that is shown first in the chemical formula is written first using the proper prefix to indicate how many atoms of that element are contained in one molecule of the compound. If there is only one atom of that element it is often found without the prefix mono. If you leave the prefix off then it is understood that you mean mono.
5. The elementís name which is written second in the chemical formula is written second in the chemical name, but in addition to the prefix indicating how many, the suffix of the elementís name is changed to -ide.
carbon becomes carbide chlorine becomes chloride
sulfur becomes sulfide oxygen becomes oxide
hydrogen becomes hydride nitrogen becomes nitride
Below is the table of prefixes that you use in Binary Molecular Compounds
MONO = ONE HEXA = SIX
DI = TWO HEPTA = SEVEN
TRI = THREE OCTA = EIGHT
TETRA = FOUR NONA = NINE
PENTA = FIVE DECA = TEN
Therefore, the following formulas of binary compounds would be written:
CCl4 carbon tetrachloride
SO2 sulfur dioxide
SO3 sulfur trioxide
CO2 carbon dioxide
CO † carbon monoxide
N2O††††† Dinitrogen oxide† (also nitrous oxide-laughing gas)
NO††††††† Nitrogen oxide† ††(also known as Nitric oxide)
NO2†††††† Nitrogen dioxide††
N2O3 dinitrogen trioxide
N2O5 dinitrogen pentoxide
†B4O10 Tetraboron decoxide
We use common names for NH3, and H2O, as shown Guideline #4.
What would be their correct binary molecular names?
Ammonia† NH3 would be Nitrogen trihydride
Water H2O †would be Dihydrogen monoxide
Sometimes they call water DHMO or in fuel they call water vapor HHO
As a spoof, the chemist at Dupont on the Delaware River created web site alerting you to the toxicity of a compound DHMO† http://www.dhmo.org Visit this site!
Methane, CH4, is the organic name for CH4, (Chapter 12) what would its inorganic name be?††† Carbon tetrahydride