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
271–280 of 407 · Easy
Question 271
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.
Question 272
1 mark · Easy
Answer and see the solution →State why potassium chloride conducts electricity when it is dissolved in water.
Question 273
3 marks · Easy
Answer and see the solution →The table shows three ionic compounds in different states:
States of ionic compounds Compound State Sodium chloride Solid Magnesium bromide Molten Potassium nitrate Aqueous (a)[1 mark]Which compound(s) in the table will conduct electricity? State all correct answers.
(b)[1 mark]State the condition required for any ionic compound to conduct electricity.
(c)[1 mark]Give one example from the table where the ionic compound will not conduct electricity, and state why.
Question 274
2 marks · Easy
Answer and see the solution →A student says that ‘solid lead(II) bromide contains charged particles, so it should conduct electricity’. Explain, giving a calculation or statement, why this is incorrect.
Question 275
2 marks · Easy
Answer and see the solution →Explain, in terms of ions, why calcium iodide conducts electricity when molten but not when solid.
Question 276
3 marks · Easy
Answer and see the solution →The table below shows whether four substances conduct electricity in different states.
Electrical conductivity of four substances Substance Solid Molten Aqueous Calcium Bromide No Yes Yes Iron(II) chloride No Yes Yes Sodium phosphate No Yes Yes Iodine No No No (a)[1 mark]From the substances in the table, identify all that are ionic compounds.
(b)[1 mark]What property do these ionic compounds share in relation to conducting electricity?
(c)[1 mark]Explain how the table helped you determine which substances are ionic.
Question 277
1 mark · Easy
Answer and see the solution →State why silver chloride does not conduct electricity in the solid state.
Question 278
3 marks · Easy
Answer and see the solution →Zinc chloride is an ionic compound.
(a)[1 mark]Describe the movement of ions in solid zinc chloride.
(b)[1 mark]Describe the movement of ions in molten zinc chloride.
(c)[1 mark]Explain how movement of ions in the molten state affects electricity conduction.
Question 279
2 marks · Easy
Answer and see the solution →Out of 5 ionic salts, 2 are molten, 1 is in aqueous solution, and the remaining 2 are solid. How many of these salts would you expect to conduct electricity? Show your working.
Question 280
5 marks · Easy
Answer and see the solution →This question is about the formation of ions and charges in ionic bonding, including magnesium oxide and another compound.
(a)[1 mark]State the charge formed on a magnesium ion in magnesium oxide.
(b)[1 mark]Magnesium is in Group 2 of the Periodic Table. Explain why the charge on a magnesium ion is the value you stated in part (a).
(c)[1 mark]State the charge formed on the oxide ion in magnesium oxide.
(d)[1 mark]When potassium forms an ionic compound with chlorine, what is the formula of the ion formed by potassium? Include its charge.
(e)[1 mark]Explain, in terms of electrons, how a chlorine atom forms an ion.