IB CHEMISTRY_BONDING TEST
Total marks: 43
Time allowed: 1 hour
1.
What is the number of sigma () and pi () bonds and the hybridization of the carbon atom in
O
H
C
O
H
Sigma
Pi
Hybridization
A.
4
1
sp2
B.
4
1
sp3
C.
3
2
sp3
D.
3
1
sp2
(Total 1 mark)
2.
How many lone pairs and bonding pairs of electrons surround xenon in the XeF4 molecule?
Lone pairs
Bonding pairs
A.
4
8
B.
0
8
C.
0
4
D.
2
4
(Total 1 mark)
3.
What is the hybridization of nitrogen atoms I, II, III and IV in the following molecules?
H 2N N H 2
I
II
HNN H
IV
III
I
II
III
IV
A.
sp2
sp2
sp3
sp3
B.
sp3
sp3
sp2
sp2
C.
sp2
sp2
sp
sp
D.
sp3
sp3
sp
sp
(Total 1 mark)
1
4.
Which statements correctly describe the NO2– ion?
I.
It can be represented by resonance structures.
II.
It has two lone pairs of electrons on the N atom.
III.
The N atom is sp2 hybridized.
A.
I and II only
B.
I and III only
C.
II and III only
D.
I, II and III
(Total 1 mark)
5.
Which allotropes contain carbon atoms with sp2 hybridization?
I.
Diamond
II.
Graphite
III.
C60 fullerene
A.
I and II only
B.
I and III only
C.
II and III only
D.
I, II and III
(Total 1 mark)
6.
Which of the following contain a bond angle of 90°?
I.
PC14+
II.
PCl5
III.
PCl6–
A.
I and II only
B.
I and III only
C.
II and III only
D.
I, II and III
(Total 1 mark)
2
7.
Based on electronegativity values, which bond is the most polar?
A.
B―C
B.
C―O
C.
N―O
D.
O―F
(Total 1 mark)
8.
What is the Lewis (electron dot) structure for sulfur dioxide?
A.
O S O
B.
O S O
C.
O
S O
D.
O
S O
(Total 1 mark)
9.
What is the molecular shape and the hybridization of the nitrogen atom in NH3?
Molecular shape
Hybridization
A.
tetrahedral
sp3
B.
trigonal planar
sp2
C.
trigonal pyramidal
sp2
D.
trigonal pyramidal
sp3
(Total 1 mark)
10.
Which types of hybridization are shown by the carbon atoms in the compound CH2 = CHCH3?
I.
sp
II.
sp2
III.
sp3
A.
I and II only
B.
I and III only
C.
II and III only
D.
I, II and III
(Total 1 mark)
3
11.
Diamond, graphite and C60 fullerene are three allotropes of carbon.
(i)
Describe the structure of each allotrope.
(3)
(ii)
Compare the bonding in diamond and graphite.
(2)
(Total 5 marks)
12.
The boiling points of the hydrides of the group 6 elements are shown below.
400
300
Boiling point / K
200
100
0
H2 O
(i)
H2 S
H 2 Se
H 2 Te
Explain the trend in boiling points from H2S to H2Te.
……………………………………………………………………………………….
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(2)
4
(ii)
Explain why the boiling point of water is higher than would be expected from the group
trend.
……………………………………………………………………………………….
……………………………………………………………………………………….
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……………………………………………………………………………………….
(2)
(Total 4 marks)
13.
(i)
State the shape of the electron distribution around the oxygen atom in the water molecule
and state the shape of the molecule.
………………………………………………………………………………………….
………………………………………………………………………………………….
(2)
(ii)
State and explain the value of the HOH bond angle.
…………………………………………………………………………………………..
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…………………………………………………………………………………………..
(2)
(Total 4 marks)
14.
(a)
An important compound of nitrogen is ammonia, NH3. The chemistry of ammonia is
influenced by its polarity and its ability to form hydrogen bonds. Polarity can be
explained in terms of electronegativity.
(i)
Explain the term electronegativity.
……………………………………………………………………………………
……………………………………………………………………………………
(2)
(ii)
Draw a diagram to show hydrogen bonding between two molecules of NH3.
The diagram should include any dipoles and/or lone pairs of electrons
……………………………………………………………………………………
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……………………………………………………………………………………
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(3)
5
(iii)
State the H–N–H bond angle in an ammonia molecule.
………………………………………………………………………………………
(1)
(iv)
Explain why the ammonia molecule is polar.
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
(1)
(b)
Ammonia reacts with hydrogen ions forming ammonium ions, NH4+.
(i)
State the H–N–H bond angle in an ammonium ion.
……………………………………………………………………………………
(1)
(ii)
Explain why the H–N–H bond angle of NH3 is different from the H–N–H bond
angle of NH4+; referring to both species in your answer.
……………………………………………………………………………………
……………………………………………………………………………………
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……………………………………………………………………………………
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(3)
(Total 11 marks)
6
15.
Draw the Lewis structures, state the shapes and predict the bond angles for the following
species.
(i)
PCl5
(3)
(ii)
SCl2
(3)
(iii)
ICl4–
(3)
(Total 9 marks)
7