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
621–630 of 991
Question 621
1 mark · Easy
Answer and see the solution →State whether giant ionic compounds have high or low melting points.
Question 622
3 marks · Easy
Answer and see the solution →Magnesium fluoride (MgF_2) is an ionic compound with a giant ionic lattice.
(a)[1 mark]State the type of structure present in magnesium fluoride.
(b)[2 marks]Explain why magnesium fluoride does not conduct electricity when solid.
Question 623
2 marks · Easy
Answer and see the solution →Potassium oxide (K_2O) is an ionic compound formed from K^+ and O^{2-} ions.
Calculate the total positive charge provided by the potassium ions in one formula unit of potassium oxide.
Question 624
2 marks · Easy
Answer and see the solution →Explain why the melting point of sodium oxide (Na_2O) is higher than that of sodium chloride (NaCl).
Question 625
3 marks · Easy
Answer and see the solution →The table shows properties of two substances.
Properties of sodium fluoride and phosphorus trichloride Substance Melting point (°C) Electrical conductivity (solid) Electrical conductivity (liquid) Sodium fluoride (NaF) 998 No Yes Phosphorus trichloride (PCl_3 -112 No No (a)[1 mark]Which substance has a giant ionic structure?
(b)[1 mark]State one piece of evidence from the table that supports your answer in (a).
(c)[1 mark]Explain why sodium fluoride conducts electricity when molten but not when solid.
Question 626
1 mark · Easy
Answer and see the solution →Name the forces that hold the ions together in a giant ionic lattice.
Question 627
3 marks · Easy
Answer and see the solution →Barium chloride (BaCl_2) is an ionic compound.
(a)[1 mark]Name the ions present in barium chloride.
(b)[1 mark]State one property of barium chloride that is linked to its structure.
(c)[1 mark]Explain how the structure of barium chloride leads to this property.
Question 628
2 marks · Easy
Answer and see the solution →Lithium oxide (Li_2O) is an ionic compound formed from lithium ions (Li^+) and oxide ions (O^{2-}).
How many electrons in total are transferred from lithium atoms to oxygen atoms to form one formula unit of lithium oxide? Show your working.
Question 629
2 marks · Normal
Answer and see the solution →Sodium chloride is an ionic compound with a giant lattice structure.
State TWO properties of sodium chloride that are linked to its giant ionic lattice, and briefly explain why the lattice causes each property.
(a)[2 marks](b)[0 marks]Question 630
4 marks · Normal
Answer and see the solution →Magnesium oxide (MgO) is a typical giant ionic compound.
(a)[1 mark]State the ions present in magnesium oxide.
(b)[2 marks]Explain why magnesium oxide has a very high melting point.
(c)[1 mark]Describe what happens to the ions when solid magnesium oxide melts.