Transcript Covalent Compounds - Broadneck High School

Covalent Compounds
Naming and Formula Writing
Covalent Compounds

Are made up of two NONMETALS.
(Both elements are from the right of the
step line (green elements shown)).
Prefixes you need to know
One – Mono
 Two – Di
 Three – Tri
 Four – Tetra
 Five – Penta

Six – Hexa
 Seven – Hepta
 Eight – Octo
 Nine – Nona
 Ten – Deca

Rules for Covalent Compounds
#1 – If the compound has only one atom of
the first element (no subscript), we just
name it normally (do not write mono….).
If there are two or more atoms of the
first element, we use a prefix to tell how
many there are (the subscript).
#2 – For the second element, we ALWAYS
use a prefix (even mono) and we change
then ending of the element to –ide.
For Example…
What would you call this compound:
CO2?
 Carbon Dioxide
 We do not call it Monocarbon Dioxide

Try these
SiCl4
 C3H9
 SO2
 N2O5

Silicon tetrachloride
 Tricarbon nonahydride
 Sulfur dioxide
 Dinitrogen pentoxide

◦ (you can drop off the –a from
penta here so you don’t have to
put two vowels together.)
Can you do it in reverse?
What is the chemical formula for
Dinitrogen Monoxide?
 N2O
 Remember, when using prefixes, it tells
you the actual subscript, you do not need
to determine charges, or criss-cross, etc.

Try these…
Carbon disulfide
 Dinitrogen monosulfide
 Diphosphorus hexaoxide
 Tricarbon octachloride

CS2
 N 2S
 P 2O 6
 C3Cl8
