PRACTICE EXAM: CHEMICAL BONDING AND STRUCTURE
(INDUSTRIAL CHEMISTRY)
Mastery of bonding and lewis structures
Question One
a) i. Explain what is meant by the term chemical bonding. [2 marks]
ii. Using necessary steps, show the Lewis dot structure of an oxygen molecule.
[4 marks]
b) Draw the cross (x) dot (.) diagram showing bonding in the following compounds.
i. Carbon (iv) oxide
ii. An ammonium ion
iii. Calcium oxide
c) i. Using the structure of propane, distinguish between line bond, condensed and
skeletal structures. [3 marks]
ii. ABE is a method for determining molecular geometry of compounds. Using this
method, deduce the molecular shape of an ammonia molecule (NH3) [3 marks]
d) i. What is meant by the term octet rule? [2 marks]
ii. Explain the effect of bond angle on the shape of molecules [4 marks]
e) i. Outline the significance of formal charge in bonding. [2 marks]
ii. Calculate the formal charge of oxygen in ozone (O3) [3 marks]
f) i. Giving suitable example, explain the meaning of the term bond order. [3 marks]
ii. By using an illustration, explain why methane is a gas while water is a liquid at
room temperature. [4 marks]
g) With the aid of structures, explain why Silcon (iv) oxide is a solid while Carbon (iv)
oxide is a gas at room temperature. [6 marks]
Question Two
a) Highlight the postulates of the VSEPR theory of bonding. [12 marks]
b) Distinguish between electronegativity, electron affinity and ionization energy and
describe their effect on bonding. [10 marks]
Question Three
a) Using the electronic structure, explain why carbon is said to be tetra-covalent. [5 marks]
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(INDUSTRIAL CHEMISTRY)
Mastery of bonding and lewis structures
Question One
a) i. Explain what is meant by the term chemical bonding. [2 marks]
ii. Using necessary steps, show the Lewis dot structure of an oxygen molecule.
[4 marks]
b) Draw the cross (x) dot (.) diagram showing bonding in the following compounds.
i. Carbon (iv) oxide
ii. An ammonium ion
iii. Calcium oxide
c) i. Using the structure of propane, distinguish between line bond, condensed and
skeletal structures. [3 marks]
ii. ABE is a method for determining molecular geometry of compounds. Using this
method, deduce the molecular shape of an ammonia molecule (NH3) [3 marks]
d) i. What is meant by the term octet rule? [2 marks]
ii. Explain the effect of bond angle on the shape of molecules [4 marks]
e) i. Outline the significance of formal charge in bonding. [2 marks]
ii. Calculate the formal charge of oxygen in ozone (O3) [3 marks]
f) i. Giving suitable example, explain the meaning of the term bond order. [3 marks]
ii. By using an illustration, explain why methane is a gas while water is a liquid at
room temperature. [4 marks]
g) With the aid of structures, explain why Silcon (iv) oxide is a solid while Carbon (iv)
oxide is a gas at room temperature. [6 marks]
Question Two
a) Highlight the postulates of the VSEPR theory of bonding. [12 marks]
b) Distinguish between electronegativity, electron affinity and ionization energy and
describe their effect on bonding. [10 marks]
Question Three
a) Using the electronic structure, explain why carbon is said to be tetra-covalent. [5 marks]
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