1. 1
   In solid sodium chloride, positively charged sodium ions and negatively charged chloride ions are arranged in a regular, repeating pattern that extends throughout the whole solid, rather than existing as separate individual particles.

   (a)

   What holds these ions together in this structure?

   [1 mark]

   • AStrong electrostatic forces of attraction between oppositely charged ions
   • BShared pairs of electrons between neighbouring ions
   • CWeak forces between individual molecules of sodium chloride
   • DDelocalised electrons moving freely through the structure

   (b)

   What term describes the type of structure formed by the huge, regularly repeating arrangement of ions found in sodium chloride?

   [1 mark]

   • AA metallic lattice
   • BA single small molecule
   • CA simple covalent structure
   • DA giant ionic structure (lattice)

   (c)

   Describe the structure of solid sodium chloride, in terms of how the ions are arranged and what holds them together.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   Magnesium oxide is another example of a giant ionic structure, made up of Mg²⁺ ions and O²⁻ ions arranged in a regular, repeating pattern.

   (a)

   In magnesium oxide, a giant ionic structure of Mg²⁺ and O²⁻ ions, in which directions do the electrostatic forces of attraction between oppositely charged ions act?

   [1 mark]

   • AOnly directly upward and downward
   • BIn all directions throughout the structure
   • COnly between one single pair of ions
   • DOnly along the surface of the solid

   (b)

   Which term correctly describes the regular, repeating arrangement of ions seen in magnesium oxide?

   [1 mark]

   • ASmall covalent unit
   • BSimple molecule
   • CGiant ionic lattice
   • DDelocalised electron cloud

   (c)

   Explain why magnesium oxide, like sodium chloride, is described as a 'giant structure' rather than as consisting of individual molecules.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A student writes the formula NaCl for sodium chloride and describes it as 'one molecule of sodium chloride', prompting a discussion of what the giant ionic structure of sodium chloride actually looks like.

   (a)

   A student writes the formula NaCl and describes it as 'one molecule of sodium chloride'. Explain why this description is not accurate.

   [3 marks]

   (b)

   Explain in detail why the strong electrostatic forces of attraction in the giant ionic lattice of sodium chloride act in all directions, rather than only between one pair of ions.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A chemistry class studies the structure of sodium chloride in detail, as the example ionic compound students are expected to be familiar with.

   (a)

   Describe the structure of sodium chloride, including the arrangement of the ions and the nature of the forces that hold the structure together.

   [6 marks]

   (b)

   Explain how the giant lattice structure and the strong electrostatic forces acting in all directions in sodium chloride relate to how ionic bonds form and hold ionic compounds together generally.

   [6 marks]

   Total for question 4: 12 marks

End of questions