Question

1. examine the prefixes in model 2 below. fill in the numerical value that corresponds

model 2 - prefixes and suffixes
prefix numerical value
mono- 1
di- 2
tri- 3
tetra- 4
penta- 5
hexa- 6
hepta- 7
octa- 8
nona- 9
deca- 10

1. what ending do all the compound names have in common?
2. when is a prefix not used in front of the name of the first element?
3. use the prefixes to name each of the following compounds:

molecular formula molecule name
pbr₃
scl₄
n₂f₂
so₃
brf

1. use the names to write the formula for each of the compounds below:

molecular formula molecule name
disulfur decafluoride
carbon tetrachloride
oxygen difluoride
dinitrogen trioxide
tetraphosphorus heptasulfide

Explanation:

1. In naming covalent compounds, the common ending for the second - element is "-ide".
2. A prefix is not used in front of the name of the first element when there is only one atom of the first element in the molecule.
3. For $PBr_3$, it is phosphorus tribromide; for $SCl_4$, it is sulfur tetrachloride; for $N_2F_2$, it is dinitrogen difluoride; for $SO_3$, it is sulfur trioxide; for $BrF$, it is bromine monofluoride.
4. For disulfur decafluoride, the formula is $S_2F_{10}$; for carbon tetrachloride, the formula is $CCl_4$; for oxygen difluoride, the formula is $OF_2$; for dinitrogen trioxide, the formula is $N_2O_3$; for tetraphosphorus heptasulfide, the formula is $P_4S_7$.

Answer:

1. -ide
2. When there is one atom of the first element.
3. Phosphorus tribromide, Sulfur tetrachloride, Dinitrogen difluoride, Sulfur trioxide, Bromine monofluoride
4. $S_2F_{10}$, $CCl_4$, $OF_2$, $N_2O_3$, $P_4S_7$