T7-CHEMICAL BONDING_QUESTIONS

CHEMISTRY DK014
MATRIKULASI KPM
SISTEM EMPAT SEMESTER (S4S)

CHAPTER 7

CHEMICAL BONDING

Face-to-Face Non Face-to-Face

11 11

At the end of this topic, the student should be able to:

7.0 CHEMICAL BONDING

7.1 Valence Electron a) Write the Lewis symbol for an atom.
and Lewis Structure b) State the octet rule.
c) Describe how atoms obtain the octet configuration.
7.2 Molecular Shape d) Describe the formation of the following bonds using Lewis dot symbol:

i) Ionic or electrovalent bond; and
ii) Covalent bond
Include the explanation in terms of difference in electronegativity.
Use only elements of Period 2 and 3.
e) Draw Lewis structure of covalent species with single, double and triple
bonds.
Use only elements of Period 2 and 3.
Include Lewis structure for simple polyatomic ions.
f) Determine the formal charge and the most plausible Lewis structure.
g) Explain the exception to the octet rule: incomplete octet, expanded octet
and odd number electrons.

a) Explain Valence Shell Electron Pair Repulsion theory (VSEPR).
b) Draw the basic molecular shapes: i) linear; ii) trigonal planar; iii)

tetrahedral; iv) trigonal bipyramidal; and v) octahedral.
c) Predict and explain the shapes of molecule and bond angles in a given

species.
[Experiment 4: Molecular Geometry]

7.3 Intermolecular a) Explain polarity and dipole moment of basic molecular shapes.
Forces b) Explain Intermolecular forces.

i) Van der Waals forces;

• dipole-dipole interaction or permanent dipole; and

• London forces or dispersion forces
ii) Hydrogen bonding

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CHEMISTRY DK014
MATRIKULASI KPM
SISTEM EMPAT SEMESTER (S4S)

TUTORIAL 7

CHEMICAL BONDING

OBJECTIVE QUESTIONS:

HOUR 9

1. The basic principle in the formation of electrovalent bond is (CLO 1, C1)

A. the sharing of electrons which leads to the sharing of atomic orbitals.
B. the transfer of electrons which leads to the formation of ions of opposite charges.
C. the formation of positive ions which are bonded together in the negative charge of

electron cloud.
D. the generation of instantaneous dipole moment arising from the differences of electron

affinities of two different atoms.

2. The electronic configurations of element P and element Q are as follows:

P: 1s2 2s2 2p6 3s2

Q: 1s2 2s2 2p5

When P and Q combine to form a compound, determine the most possible formula of this
compound and the type of bonding between them.

(CLO 1, C2)

Formula Types of bonding

A. PQ2 covalent
B. P2Q covalent
C. PQ2 electrovalent
D. P2Q3 electrovalent

3. The Lewis structure of SOCl2 is given as follows:

O

Cl S Cl

The formal charges on sulphur, chlorine and oxygen are (CLO 4, C3)
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Sulphur Chlorine Oxygen

A. 0 00
B. -1 +2 -1
C. +2 -1 -1
D. +2 -2 0

CHEMISTRY DK014
MATRIKULASI KPM
SISTEM EMPAT SEMESTER (S4S)

4. The following Lewis structures obey the octet rule, EXCEPT (CLO 1, C1)

A. OF2 C. BF3
B. ClO2+ D. CCl4

5. Choose the INCORRECT statement about the triple bond in the nitrogen molecule.
(CLO 1, C2)

A. has a total of six electrons.

B. consists of 1  bond and two  bonds.
C. it is shorter than the N – N single bond.
D. made up of 3 non-bonding electron pairs.

6. Choose the CORRECT representation of the bond formed in sodium iodide.

(CLO 1, C2)

A. I C.

Na Na I

B. + - D. + 2- +

Na I Na I Na

7. Which of the following statements is NOT TRUE regarding carbon dioxide molecule?
(CLO 1, C1)

A. It is a non-polar molecule.
B. The carbon-oxygen bonds are polar.
C. The carbon-oxygen bond is an ionic bond.
D. The carbon-oxygen bonds are made up of  and π bonds.

8. What is the main use of VSEPR theory? (CLO 1, C1)

A. predicting bond angles C. predicting dipole moments
B. predicting bond lengths D. predicting electronegativities

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CHEMISTRY DK014
MATRIKULASI KPM
SISTEM EMPAT SEMESTER (S4S)

9. What is the bond angle x in CF4?

(CLO 1, C2)

F
x

FCF

F

A. Less than 90o C. Exactly 109.5o
B. Exactly 90o D. More than 109.5

10. What type of bond can be found in ice? (CLO 1, C1)

A. covalent bond only C. ionic and covalent bonds
B. hydrogen bond only D. hydrogen and covalent bonds

SUBJECTIVE QUESTIONS:

HOUR 1

1. (a) What is a Lewis dot symbol? Give an appropriate example.

(b) State the octet rule and describe how Cl2 obtain the octet configuration.
(CLO 1, C1 & C2)

2. Complete the table below:

Element Electron Configuration Group Lewis dot symbol

28 Si
14

16 O
8

40 Ar
18

27 Al
13

2142Mg

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CHEMISTRY DK014
MATRIKULASI KPM
SISTEM EMPAT SEMESTER (S4S)

(CLO 4, C3)

HOUR 2

3. (a) What is an ionic bond?

(b) Using sodium chloride, NaCl as an example, describe the formation of ionic bonds in

the compound. (CLO 1, C1 & C2)

4. Using Lewis dot symbol show the formation of ionic bond between the following pairs of
elements.

(a) Mg and Br (CLO 4, C3)
(b) Al and O
(c) Ba and O
(d)

5. (a) What is a covalent bond?

(b) Using hydrogen fluoride, HF as an example, describe the formation of covalent bond in
the compound.

(CLO 1, C1 & C2)

HOUR 3

6. Show how a covalent bond is formed in the following molecules using Lewis structure.

(a) F2 (CLO 1, C2)
(b) CH4
(c) N2

7. Show all the basic steps in writing the Lewis structure of PF3.

HOUR 4 (CLO 1, C2)
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8. Draw the simplest Lewis structure for each of the following molecules.

Determine whether these molecules satisfy the octet rule.

(a) NCl3 (e) AlBr3
(b) ClF3 (f) SeF4
(c) BCl3 (g) NO
(d) H2S (h) CN-

CHEMISTRY DK014
MATRIKULASI KPM
SISTEM EMPAT SEMESTER (S4S)

(i) NO+ (j) O3

(CLO 4, C3)

HOUR 5
9. Draw all possible Lewis structures for POCl3. Select the best Lewis structure.

(CLO 4, C3)

HOUR 6

10. Draw and determine the molecular geometry of the species in which around the central atom
there are

(a) two single bonds (d) five single bonds

(b) three single bonds. (e) six single bonds

(c) four single bonds

(CLO 1, C2)

11. Using VSEPR model, predict the molecular geometries of:

(a) NO2+ (d) COCl2

(b) PBr5 (c) ClO4-

(c) O2 (d) SbF6-

(CLO 4, C3)

HOUR 7

12. (a) Define a dipole moment.

(b) Explain whether each of the following molecules is polar or non-polar.

i. HBr iii. SF6

ii. BF3 iv. NH3

(CLO 1, C1 & C2)

42

CHEMISTRY DK014
MATRIKULASI KPM
SISTEM EMPAT SEMESTER (S4S)

13. (a) What are dipole-dipole forces?

(b) How do polar molecules attract each other?
Explain how London forces arise between non-polar molecules.

(CLO 1, C1 & C2)
HOUR 8
14. (a) State whether these following molecules are polar or non-polar and name the type of
van der Waals forces that exist between them.

i. I2 iv. H2S
ii. SO2 v. C6H6
iii. CH4 vi. H2O

(CLO 1, C1 & C2)

(b) Describe the hydrogen bond with illustration.

(CLO 1, C2)

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