Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Principles of Chemistry
991 practice questions
Topics covered
- States of Matter102 practice questions
- Elements, Compounds and Mixtures69 practice questions
- Atomic Structure108 practice questions
- The Periodic Table103 practice questions
- Chemical Formulae, Equations and Calculations Part 119 practice questions
- Chemical Formulae, Equations and Calculations Part 2144 practice questions
- Ionic Bonding143 practice questions
- Covalent Bonding68 practice questions
- Metallic Bonding19 practice questions
- Electrolysis198 practice questions
Practice questions
101–110 of 161 · Hard
Question 101
5 marks · Hard
Answer and see the solution →Sodium sulfide (Na_2S) and aluminium oxide (Al_2O_3) are both giant ionic compounds.
(a)[2 marks]Describe the arrangement of ions in the lattice of a giant ionic compound.
(b)[3 marks]Explain, using your knowledge of structure, why the melting point of aluminium oxide is much higher than that of sodium sulfide.
Question 102
2 marks · Hard
Answer and see the solution →State and explain whether potassium iodide (KI) has a high or low melting point. Refer to its structure in your answer.
Question 103
2 marks · Hard
Answer and see the solution →Explain, in terms of the forces present, why ionic compounds such as sodium chloride have high boiling points.
Question 104
5 marks · Hard
Answer and see the solution →Crystals of sodium chloride are often seen as large, regular cubes under the microscope.
(a)[1 mark]State what is meant by the term 'crystalline' when describing a substance.
(b)[2 marks]Describe the arrangement of ions in the giant ionic lattice of sodium chloride as it relates to its crystalline appearance.
(c)[2 marks]Explain why the regular arrangement of ions results in sodium chloride crystals having a regular shape.
Question 105
2 marks · Hard
Answer and see the solution →Describe the arrangement of sodium and chloride ions in the giant ionic lattice of sodium chloride.
Question 106
2 marks · Hard
Answer and see the solution →Explain, in terms of ions, why solid sodium oxide does not conduct electricity.
Question 107
5 marks · Hard
Answer and see the solution →Lead(II) nitrate is an ionic compound. It can be either solid, molten, or dissolved in water.
(a)[2 marks]State whether lead(II) nitrate conducts electricity in each of the following states:
State Does it conduct? (Yes/No) Solid Molten Aqueous solution (b)[3 marks]Explain, in terms of ions, why lead(II) nitrate behaves in this way in these states.
Question 108
2 marks · Hard
Answer and see the solution →State the two conditions under which an ionic compound can conduct electricity.
Question 109
7 marks · Hard
Answer and see the solution →Sodium chloride (NaCl) is a typical ionic compound. The arrangement of ions in its structure and the structure's properties explain many features of ionic solids.
(a)[2 marks]Describe how the ions are arranged in the giant ionic lattice of sodium chloride.
(b)[2 marks]Explain why sodium chloride has a high melting point, referring to its structure.
(c)[2 marks]State one feature of the overall appearance of pure sodium chloride crystals and relate it to the arrangement of ions in its lattice.
(d)[1 mark]Give one other property (besides melting point) that is explained by the structure of giant ionic lattices, and state how the arrangement of ions accounts for it.
Question 110
7 marks · Hard
Answer and see the solution →Magnesium oxide (MgO) and sodium chloride (NaCl) both form giant ionic lattices, but their melting points are very different.
(a)[2 marks]Describe the structure of a giant ionic lattice, using magnesium oxide as an example.
(b)[3 marks]Explain why magnesium oxide has a much higher melting point than sodium chloride. Refer to the types of ions present and their charges.
(c)[2 marks]Both substances conduct electricity when molten but not when solid. State and explain why.