Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
The physical properties of ionic substances
19 practice questions
Practice questions
1–8 of 8 · Easy
Question 1
1 mark · Easy
Answer and see the solution →State why crystals of sodium chloride have a regular shape.
Question 2
3 marks · Easy
Answer and see the solution →(a)[1 mark]Name the two types of ions found in sodium chloride.
(b)[1 mark]Describe the arrangement of ions around a single sodium ion in the lattice.
(c)[1 mark]State whether sodium chloride exists as molecules or as a giant ionic lattice.
Question 3
2 marks · Easy
Answer and see the solution →Ionic compounds often form crystals. Explain why the crystalline property is linked to the structure of their ions.
Question 4
3 marks · Easy
Answer and see the solution →The table shows part of the arrangement of ions around a sodium ion in sodium chloride:
Ion Count Distance from central sodium ion (pm) Chloride ion 6 280 Sodium ion 12 400 Chloride ion 8 490 (a)[1 mark]What type of lattice is formed by sodium chloride?
(b)[1 mark]How many chloride ions are nearest to each sodium ion?
(c)[1 mark]Describe how the pattern of ions continues in the lattice.
Question 5
1 mark · Easy
Answer and see the solution →State why ionic compounds such as sodium chloride have high melting points.
Question 6
3 marks · Easy
Answer and see the solution →(a)[1 mark]What does it mean if a substance is described as 'crystalline'?
(b)[2 marks]Explain how the structure of sodium chloride leads to its crystalline appearance.
Question 7
2 marks · Easy
Answer and see the solution →The strong electrostatic forces between ions in an ionic lattice result in high melting points for ionic compounds.
Suppose it takes 780 kJ of energy to melt 1 mole of sodium chloride (NaCl). Calculate the energy required to melt 2.5 moles of sodium chloride.
Show your working and state the unit.
Question 8
2 marks · Easy
Answer and see the solution →In sodium chloride, each sodium ion (Na^+) is surrounded by 6 chloride ions (Cl^-).
Calculate the total number of chloride ions immediately surrounding sodium ions in a lattice that contains 4 sodium ions.
Show your working.