ANSWER KEY
Bonding Review Station #1:
1. What charge does a magnesium ion have?
+2
2. Write the formula for potassium sulfide.
K2S
3. What charge will arsenic form when it becomes an ion?
Explain how this ion will form.
-3. This ion forms when arsenic gains three electrons.
4. Describe two similarities and two differences between
an ion and the atom from which it forms.
Similarities: each has the same number of protons and
neutrons
Differences: the number of electrons changes when an
atom becomes an ion, the size of the ion is different
from that of the atom
5. What is the octet rule?
The octet rule states that atoms tend to gain or lose
electrons in order to achieve a full set of valence
electrons.
Bonding Review Station #2:
1. Ionic bonds are formed by a TRANSFER of electrons.
2. Anions are attracted to a POSITIVE charge.
3. Melting points of ionic compounds are typically
(higher/lower) than those of covalent compounds.
4. What does it mean to say that an ionic compound is
“brittle”?
Brittle means to break apart easily and in smaller
crystalline pieces.
5. Why do ionic compounds conduct electricity only when in
a melted or dissolved state?
In these states, the electricity is able to flow as the
ions themselves also have the ability to move around.
ANSWER KEY
6. Describe the structure of ionic compounds and how this
causes two of their properties.
Ionic compounds are typically crystal lattices. This
structure makes them rigid and brittle, makes them have
high melting and boiling points, and makes it
impossible for them to conduct electricity unless
molten or aqueous.
Bonding Review Station #3:
1. Covalent compounds are formed when electrons are SHARED
between two or more atoms.
2. Most atoms are stable when they have 8 valence
electrons.
3. A nonpolar covalent bond contains atoms having an
electronegativity difference that is between 0.0 and
0.3.
4. A polar covalent bond contains atoms having an
electronegativity difference that is between 0.3 and
1.7.
5. Describe what is happening in a polar covalent bond.
In a polar covalent bond, the electrons are shared
unequally. This inequality leads to the formation of
partial charges, which makes the molecule a dipole.
Bonding Review Station #4:
1. Draw the Lewis structure for the bond that forms
between lithium and bromine. List the ions that result,
the chemical formula, and the name of the compound.
Li
Li+1 Br-1
Br :
LiBr
lithium bromide
ANSWER KEY
2. Draw the Lewis structure for the bond that forms
between calcium and nitrogen. List the ions that
result, the chemical formula, and the name of the
compound.

Ca
N:


Ca
N:
3(Ca+2) 2(N-3)
Ca3N2
calcium nitride

Ca
3. Draw the Lewis structure for HCl. Name this molecule.
H – Cl
hydrogen monochloride
4. Draw the Lewis structure for SiH4. Name this molecule.
H
Silicon tetrahydride
H
Si H
H
Bonding Review Station #5:
Name the following:
1. Rb2O
2. CCl4
3. P2O5
4. Mg3P2
5. FeBr3
6. Ca3(PO4)2
rubidium oxide
carbon tetrachloride
diphosphorus pentoxide
magnesium phosphide
iron (III) bromide
calcium phosphate
Bonding Review Station #6:
What type of bond exists between the following atoms?
1. C-H
2. Rb-O
polar covalent
ionic
(difference of 0.4)
(difference of 2.7)
ANSWER KEY
3. F-F
nonpolar covalent (difference of 0.0)
4. Si-Cl
polar covalent (difference of 1.2)
5. Why do ionic bonds tend to form between a metal and a
nonmetal?
Metals tend to have valence shells that are less than
half-filled, so it is easier for them to give away
electrons to achieve a full octet. Nonmetals, on the
other hand, have valence shells that are at least halffilled and therefore tend to gain electrons to achieve
an octet.
6. Why do covalent bonds tend to form between two nonmetal
atoms?
Nonmetals have valence shells that are half or more
than half-filled, so they don’t give away (lose)
electrons. Instead, they bond so that they can share
electron pairs to achieve a full valence shell and
satisfy the octet rule.
ANSWER KEY
Name
Formula
Lewis
Structure
VSEPR Shape
Polarity
Tetrahedral
nonpolar
Trigonal
planar
nonpolar
Trigonal
pyramidal
polar
Linear
nonpolar
Bent
polar
H
Silicon
tetrafluoride
SF4
H
Si
H
H
H
Boron
trihydride
B
BH3
H
H
..
H
Nitrogen
trihydride
N
H
NH3
H
(ammonia)
..
..
:O = C = O:
Carbon
dioxide
CO2
H
Dihydrogen
monosulfide
..
S:
H
H2 S