Complete the table for the substances shown in diagrams A to E. In each case, state whether the diagram represents a solid, a liquid or a gas. (Part of the table is already completed for you.)
Diagram
A B C D E
3. Final Examination 2019, Question 15
The diagrams below show the arrangement of particles in the elements aluminium and chlorine at room temperature.
Aluminium Chlorine Solid, liquid or gas
Solid
)Fig. 14.16
a. Which of these elements is a solid at room temperature? Justify your answer. b. The table shows some of the properties of three elements from the periodic table.
Element 1 Element 2 Element 3
Melting point (°C) Boiling point (°C) Conductor of electricity 1538 −7
2862 59
−101 −34
Yes No No
Which element (1, 2 or 3) is a liquid at room temperature (20 °C)? Justify your answer.
4. Final Examination 2022, Question 13 A student carried out a series of experiments to investigate the properties of sucrose (table sugar). In the first experiment, the student investigated the melting point of sucrose.
Two metal cubes of equal volume were placed on a hotplate as shown in the diagram. One was made of zinc (Zn) and the other was made of aluminium (Al). One gram of sucrose was placed on top of each cube and the hotplate was turned on.
Metal cube (Zn)
Sucrose
Metal cube (AI)
Hot plate
)Fig. 14.17
a. What is meant by the melting point of a substance? b. Explain why the sugar melted but the metals did not.
j Go to page 75 of your Assessment Book to answer more exam-style questions. 146 Elements of Science