Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
The Alkali Metals
85 practice questions
Topics covered
Practice questions
31–40 of 85
Question 31
3 marks · Normal
Answer and see the solution →When potassium and sodium are each added separately to water, potassium reacts much more vigorously than sodium.
Use knowledge of their atomic structures to explain fully why potassium is more reactive than sodium.
Question 32
4 marks · Normal
Answer and see the solution →The table shows the number of electron shells and the speed of reaction with water for the three Group 1 metals:
Metal Number of electron shells Relative speed of reaction (1=slow, 3=fast) Lithium 2 1 Sodium 3 2 Potassium 4 3 (a)[1 mark]Describe the pattern shown between number of electron shells and speed of reaction.
(b)[2 marks]Suggest how the electronic configuration of rubidium (Rb), the next Group 1 metal, might affect its reaction with water.
(c)[1 mark]State what you would expect the relative speed of rubidium's reaction with water to be compared to potassium.
Question 33
1 mark · Normal
Answer and check →Why does the reactivity of Group 1 elements increase as you go down the group?
- A.The outer electron becomes harder to lose because it is closer to the nucleus.
- B.More electron shells mean the outer electron is further from the nucleus and lost more easily.
- C.The atoms gain more protons so become less reactive.
- D.Atoms of Group 1 elements get lighter down the group.
Question 34
2 marks · Normal
Answer and see the solution →Explain why lithium reacts more slowly than sodium when added to water.
Question 35
4 marks · Normal
Answer and see the solution →Group 1 metals lose their outer electron in chemical reactions.
(a)[2 marks]Describe the difference in atomic structure between sodium and potassium.
(b)[2 marks]Explain how this difference affects their reactivity.
Question 36
2 marks · Hard
Answer and see the solution →Explain, in terms of their electronic configurations, why a rubidium atom loses its outer electron more easily than a sodium atom.
Question 37
5 marks · Hard
Answer and see the solution →(a)[1 mark]State the electronic configuration of a potassium atom.
(b)[2 marks]Using the electronic configurations, compare the positions of the outer electrons in sodium and potassium atoms.
(c)[2 marks]Explain, with reference to their atomic structure, why potassium reacts more vigorously with water than sodium does.
Question 38
2 marks · Hard
Answer and see the solution →Why is the outer electron in a caesium atom less strongly attracted to the nucleus than in a lithium atom? Give two reasons.
Question 39
1 mark · Easy
Answer and see the solution →State what you would see when a piece of freshly cut lithium is left exposed to air.
Question 40
3 marks · Easy
Answer and see the solution →Sodium chloride, potassium bromide, and lithium iodide are all compounds of Group 1 metals.
(a)[1 mark]State the usual colour of sodium chloride.
(b)[1 mark]Which one of these compounds is most likely to be soluble in water?
(c)[1 mark]Explain why most Group 1 metal compounds form colourless solutions.