Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Inorganic Chemistry
869 practice questions
Topics covered
- The Alkali Metals85 practice questions
- The Halogens86 practice questions
- Gases in the Atmosphere86 practice questions
- Reactivity Series163 practice questions
- Extraction and Uses of Metals128 practice questions
- Acids, Alkalis and Titrations83 practice questions
- Acids, Bases and Salt Preparations156 practice questions
- Chemical Tests68 practice questions
Practice questions
371–374 of 374 · Normal
Question 371
8 marks · Normal
Answer and see the solution →The following experiment investigates the reactions of alkali metals and halogens, and how their reactivity relates to redox processes.
(a)[2 marks]A student leaves a freshly cut piece of sodium exposed to air and measures how long it takes to lose its shine. Another student does the same for potassium. Explain, using observations and knowledge of the alkali metals’ reactions with air, which metal loses its shine faster and why.
(b)[1 mark]The following table shows the time taken (in seconds) for lithium, sodium, and potassium to lose their shine when exposed to air:
Time taken for Group 1 metals to lose shine in air Metal Time to lose shine / s Lithium 70 Sodium 20 Potassium 4 (c)[2 marks]When potassium reacts with bromine, a halide salt is formed. Write a balanced symbol equation for this reaction, including state symbols.
(d)[3 marks]A displacement reaction occurs when chlorine water is added to a solution of potassium bromide. Use a labelled electron transfer diagram or a written explanation to describe how this reaction can be viewed as a redox reaction.
Question 372
8 marks · Normal
Answer and see the solution →Answer all parts about compounds and predicted properties in Group 1 and Group 7.
(a)[2 marks]State the typical colour and solubility in water of sodium oxide.
(b)[2 marks]Potassium manganate(VII) is a purple compound. State which ion gives rise to the colour, and what colour you would observe if pure potassium chloride is dissolved in water.
(c)[2 marks]Predict the colour and physical state at room temperature of astatine, the halogen below iodine.
(d)[2 marks]Predict whether sodium astatide would be soluble in water, and what colour its solution would be. Explain your reasoning.
Question 373
8 marks · Normal
Answer and see the solution →Read each question and give concise answers about an unobserved alkali metal and explanations for group reactivity.
(a)[3 marks]Francium is an alkali metal that has not been observed directly. Predict two physical properties and one likely reaction with water of francium, based on trends in Group 1.
(b)[2 marks]Explain in terms of electronic configuration why francium is expected to be more reactive than potassium.
(c)[3 marks]The reactivity of halogens decreases down the group. Explain why, in terms of electronic configuration, chlorine reacts more readily than iodine.
Question 374
8 marks · Normal
Answer and see the solution →This question is about trends and reactions involving Group 1 alkali metals and Group 7 halogens.
(a)[1 mark]Potassium reacts vigorously with water to produce potassium hydroxide and hydrogen gas. Write a balanced chemical equation for this reaction.
(b)[1 mark]Describe one difference you would observe in the reaction of potassium with water compared to that of lithium with water.
(c)[2 marks]Explain, using ideas about atomic structure, why potassium is more reactive than sodium.
(d)Chlorine water is added to a solution of potassium iodide.
(i)[2 marks]Write an ionic equation for the reaction that occurs.
(ii)[2 marks]State one visible observation when chlorine water is added to potassium iodide solution and explain why this occurs, referring to relative reactivity.