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SCH3U
Sample Chapter 2 Test
This test may be longer than the test you get on Thursday.
Thursday’s test also may contain questions of slightly different formats.
The basic information will be the same.
1) How is an ordinary covalent bond different from a co-ordinate covalent bond.
In a co-ordinate bond, both electrons come from the same atom.
2) Draw a Lewis diagram for the molecule HO. Label one of each of the following types of electrons:
lone pair, bonded pair, and unpaired (3 points).
3) State whether the following bonds will be ionic, polar covalent, or covalent. If the bond is polar
covalent or ionic, state which atom will have the partial or full negative charge.
a) Br-S
b) N-I
c) O-O
d) H-F
non-polar
polar
non-polar
polar
4) Use Lewis diagrams to show the molecules that would form between the following atoms.
a) Cl & itself
b) C & S
c) O & I
d) Si & Cl
5) Use Lewis diagrams to show how the following elements could combine to form ionic compounds
and then give the formula that results. a) Li & I
b) Ca & Br
c) Rb & S
LiI
CaBr2
Rb2S
6) Draw a Lewis structure for the following molecule following the rules for complex molecules. Give
the number of ordinary and co-ordinate covalent bonds present.
PO33-
There are no co-ordinate covalent bonds.
7) Give the Lewis structure, compound type (ionic, polar, non-polar), shape and shape code (if
molecular), for each of the following.
a) CH4
b) KI
c) CH2F2
d) SO3
e) N2
non-polar
ionic
polar
non-polar
non-polar
tetrahedral
tetrahedral
flat triangle
diatomic
AX4E0
AX4E0
AX3E0
AX1E1 (1 bond, but it is a triple bond)
2 single bond
1 double bond
f) HCl
polar
diatomic
AX1E3
g) BeH2
non-polar
linear
AX2E0
h) H2S
polar
bent
AX2E2
i) HCN
polar
linear
AX2E0
j) NH3
polar
trigonal pyramid
AX3E1
8) Identify one compound from question 7 that would have each of the following inter-particle
forces. Chose a different compound for each force.
a) ionic bonds
b) London forces
c) Hydrogen bonds
d) dipole/dipole forces
KI
CH4
NH3
H2S
9) a) Give an example of a substance that would be held together entirely by covalent bonds.
Diamonds, Quartz
b) Give one physical property that would result from such a configuration.
Very hard, high melting point.
10) Arrange the forces in question 8 and 9 in order from weakest to strongest (some may be the same).
London forces; dipole/dipole forces; Hydrogen bonds; Covalent and Ionic
11) Which compound in each of the following pairs of compounds will have the higher melting point?
Give the deciding factor in each case.
a) NH3 and PH3
b) LiBr and SBr2
c) BCl3 and BCl2F
d) C4H10 and C12H26
NH3; polar
PH3 is not polar
e) H2O and H2S
H2O; H-bonds
H2S dipole/dipole
LiBr; ionic
SBr2 is polar
BCl2F; polar
BCl3 is non-polar
f) CO2 and HCN
HCN; polar
CO2 non-polar
g) H2O and C45H92
C45H92
the large London
forces are stronger
than H2O H-bonds
C12H26; larger molecule
h) OCl2 and CO2
OCl2; polar
CO2 is non-polar
12) Identify each of the following compounds as being soluble in water or soluble in cyclohexane (a
non-polar solvent).
a) O2
b) KCl
c) C2H5OH
d) C3H8
e) CCl4
f) NH3
cyclohexane
non-polar
water
ionic
water
polar
cyclohexane
non-polar
cyclohexane
non-polar
water
polar
You also should be able to generate chemical formulas given the compound name and to name a
compound if given its formula. Questions 15, 16, and 17 on pages 103 and 104 are good practice for
this.
15) a) NaHSO4
f) NaClO
k) Al2O3
b) NaOH
g) S8
l) KOH
c) CO2
h) KNO3
m) H2CO3
d) HC2H3O2
i) H3PO4
e) not on our list
j) I2
16) a) MgBr2
f) Ag2CO3
k) MgO
p) Zn(ClO)2
u) NaClO
z) BaCO3
b) CS2
g) Al(ClO4)3
l) N2O
q) Pb(ClO4)4
v) OCl2
c) Hg(NO2)2
h) CuSO4
m) FeSO5
r) PBr5
w) SnBr2
d) HCl
i) SO3
n) H2CO3
s) AsCl5
x) H2SO4
e) LiOH
j) NiPO4
o) Ca(OH)2
t) Bi(NO3)3
y) KOH