IGCSE Chemistry Extended 2.5 Simple molecules and covalent bonds Topic Practice

CAIE IGCSE Chemistry Extended 2.5 Simple molecules and covalent bonds question practice helps you revise this syllabus point with the course map in view. Use this page to focus on one topic, check the style of questions available, and connect each attempt back to the knowledge area it is testing.

EduNinja keeps Chemistry practice aligned to CAIE at Extended level, so you can move from topic review into exam-style question bank work without losing the syllabus structure. Start with a small set, mark the weak steps, then return to nearby topic links when a definition, graph, calculation, or explanation needs repair.

[Maximum number: 1]

The following table gives information about six substances.

Which substance could be propane?

[Maximum number: 5]

This question is about gases.

(a)

$\mathrm{NF}_{3}$ has covalent bonds.

[ 5 ]

(i)

What is a covalent bond?

[ 2 ]

(ii)

Complete the dot-and-cross diagram to show the electron arrangement in a molecule of $\mathrm{NF}_{3}$ .
Show outer shell electrons only.

[ 3 ]

[Maximum number: 2]

Complete the diagram to show the electron arrangement in a carbon dioxide molecule. Show the outer shell electrons only.

[Maximum number: 2]

This question is about gases found in clean, dry air and gases found in polluted air.

Complete the dot-and-cross diagram in Fig. 1.1 for a molecule of $\mathrm{CO}_{2}$ . Show outer shell electrons only.

Fig. 1.1

[Maximum number: 1]

Ammonia, $\mathrm{NH}_{3}$ , is a covalent molecule.
Which diagram shows the outer-shell electron arrangement in a molecule of ammonia?

[Maximum number: 1]

The table shows the melting points, boiling points and electrical conductivities of six substances, D, E, F, G, H and I.

Identify the substance, D, E, F, G, H or I, which is:

a solid consisting of simple molecules at $25^{\circ} \mathrm{C}$ . ..... [1]

[Maximum number: 3]

The table shows the melting points, boiling points and electrical conductivities of six substances D, E, F, G, H and I.

Choose substances from the table which match the following descriptions. Each substance may be used once, more than once or not at all.

Which three substances contain simple molecules?

[Maximum number: 1]

Which diagram shows the arrangement of the outer shell electrons in a molecule of water?

[Maximum number: 1]

Which row describes the formation of single covalent bonds in methane?

both atoms gain a
noble gas electronic structure

both atoms have the same number
of electrons in their outer shell

both atoms gain a
noble gas electronic structure

both atoms have the same number
of electrons in their outer shell

[Maximum number: 1]

The table shows the electronic structure of four atoms.

Which two atoms combine to form a covalent compound?

W and X

W and Y

X and Y

X and Z

0 selected

Question 1(d)

Question 1

Question 1(b)

Question 1(b)(i)

Question 1(b)(ii)

Question 1(d)

Question 1(h)

Question 3

Question 2(a)(iii)

Question 2(c)

Question 4

Question 5

Question 5