The table shows some properties of four substances, W, X, Y and Z.
| Substance | Melting point / °C | Boiling point / °C | Conducts electricity when solid | Conducts electricity when liquid |
|---|---|---|---|---|
| W | 1710 | 2230 | no | no |
| X | −130 | 36 | no | no |
| Y | 801 | 1413 | no | yes |
| Z | −7 | 59 | no | no |
Give the letters of the two substances that are liquids at 25 °C.
Give the letter of the substance with the weakest forces between its particles. Justify your answer.
Y is an ionic compound and Z is a simple molecular substance. Explain why much more energy is needed to melt Y than to melt Z.
Deduce the type of structure of W. Justify your answer using the data in the table.
The particle model shows particles in solids, liquids and gases as small solid spheres. Give two limitations of this model.
53 exam-style questions on Edexcel GCSE Chemistry 3.1 States of matter, covering 3.1.1 The three states of matter and changes of state. Each one has a worked solution and a mark scheme showing where the marks go.