Page 12 - ACE YR IGCSE A TOP APPROACH TO CHEM

8 A student carried out an experiment to investigate the melting point of naphthalene and wax.
A heating curve for naphthalene and wax is shown below.

Temperature / °C
90

Naphthalene
80

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70
Wax

60

50
0 2 4 6 8 10
Time / minutes

(a) What is the melting point of naphthalene?

[1]

(b) Compare the differences between arrangement and movement of particles for solid
naphthalene and liquid naphthalene.

[2]

(c) Wax is an impure substance. How to distinguish it from the graph?

[1]
[Total: 4]

Clone May / June 2015
9 Particles diffuse. This is how we can smell the food that is cooking in the kitchen.

(a) Explain, using the kinetic particle theory, why particles diffuse.

[2]

Chapter 1 States of Matter 9

Chapter 1.indd 9 3/4/22 11:57 AM