Ionic Compounds II and Molecular Compounds Answers
Name:__________________________
Period:____________
Part A: Ionic Compounds II
1. How many moles of atomic entities are there in 1.5 mol. of each following compound?
a. Iron(II) bicarbonate
b. Barium phosphate
c. Cobalt(III) sulfite
d. Aluminum dichromate
e. Cesium oxalate
f.
Copper(II) nitride
2. For each of the compound in Q1, calculate molar mass.
a. Iron(II) bicarbonate
b. Barium phosphate
c. Cobalt(III) sulfite
d. Aluminum dichromate
e. Cesium oxalate
f.
Copper(II) nitride
3. For each of the compound in Q1, calculate mass for each atomic entity in 10.00 grams of corresponding
compound.
a. Iron(II) bicarbonate
b. Barium phosphate
c. Cobalt(III) sulfite
d. Aluminum dichromate
e. Cesium oxalate
f.
Copper(II) nitride
Part B: Binary Molecular Compounds
Binary molecular compounds are composed of two types of atoms connected by covalent bonds.
The following are the conventions used in naming binary molecular compounds:
a) Select the element with lower electronegativity, put it first and use the element name.
b) The element with higher electronegativity is put in the 2 nd place and its name changed to end
with -ide. [So far, quite similar to the binary ionic compounds. But the problem is that there
are no charges associated with molecular compounds since there is no complete transfer of
valence electrons. Hence, number of atoms associated with each compound has to be stated
clearly.]
c) Use prefixes (see table below) to indicate how many atoms are present in each molecule for
molecular compounds. Only exception is mono- prefix for the first element is omitted.
Number
1
2
3
4
5
6
7
8
9
10
Prefix
monoditritetrapentahexaheptaoctanonadeca-
Examples:
 NO: nitrogen monoxide [mononitrogen monoxide, the mono- prefix for nitrogen(the
first element) is dropped. However, the mono- prefix for the 2nd element has to be
kept.]
 S2F4: disulfur tetraflouride
Write out the name for the following compounds.
1. CO ___________________
2.
CO2_________________________________
3. N2O___________________
4.
N2O4_______________________________
5.
NO2_________________________________
6.
CF4__________________________________
7.
BCl3_________________________________
8.
PCl5_________________________________
9.
SF6__________________________________
10.
S2O3_________________________________
Write out the formulas for the following.
1. phosphorus trichloride ________
2. dinitrogen pentoxide__________
3. nitrogen triiodide ____________
4. sulfur tetrabromide __________
5. selenium hexachloride ________
6. nitrogen monoxide __________
7. sulfur dioxide ______________
8. boron trifluoride ___________
9. carbon tetrachloride _________
10. arsenic pentabromide _________
Extension Question:

How could one tell the difference between ionic and molecular compounds? Are there any exception(s) to
the rule?