Question 1

Various options are provided as possible answers to the following questions. Each
question has only ONE correct answer. Choose the answer and write only the
letter (A–D) next to the question number (1.1–1.10) in the ANSWER BOOK, for
example 1.11 E.

1.1 Air can be classified as a/an …
A element.
B compound.
C homogenous mixture.
D heterogeneous mixture. (2)

1.2 The graph below shows the heating curve of a substance.

In which part(s) of the graph does the substance gain kinetic energy?
A BC only
B CD only
C AB and CD
D AB, BC and CD (2)

1.3 In which ratio will group (I) elements react with group (VI) elements?
A 2 : 1
B 1 : 6
C 6 : 1
D 1 : 3 (2)

1.4 What is the total number of nucleons in the ion of calcium when calcium loses
two electrons to form Ca²⁺?
A 40
B 18
C 22
D 20 (2)


1.5 Which ONE of the following groups of elements shows the CORRECT trend
of the density of metals?
A Rb < K < Na < Li
B K < Na < Li < Rb
C Li < Na < K < Rb
D Na < Li <Rb < K (2)


1.6 A learner used the flow chart below to classify some examples of substances
P, Q and R.

1.7 In a 20 g sample of molecules, which sample below has the greatest number
of moles?
A NH₃
B N₂
C CO₂
D H₂ (2)



1.8 Carbon dioxide can change directly from the solid phase to the gas phase.
This process is known as …
A sublimation.
B evaporation.
C decomposition.
D melting. (2)


1.9 The chemical name for Fe₂(SO₄)₃ is …
A iron sulphite.
B iron(III) sulphate.
C iron(II) sulphate.
D iron sulphide. (2)


1.10 All the soil on Earth is known as the …
A atmosphere
B biosphere
C lithosphere.
D hydrosphere.