Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
Explaining the increase in reactivity
19 practice questions
Practice questions
1–8 of 8 · Normal
Question 1
2 marks · Normal
Answer and see the solution →State how the electronic configuration changes as you go down Group 1, and explain how this relates to the change in reactivity.
Question 2
4 marks · Normal
Answer and see the solution →The Group 1 elements react by losing their single outer electron.
(a)[1 mark]Draw and label the electronic configuration for a sodium atom (Na).
(b)[2 marks]Explain, in terms of its electronic configuration, why sodium is more reactive than lithium.
(c)[1 mark]State what happens to the attraction between the nucleus and outer electron as you move from sodium to potassium.
Question 3
3 marks · Normal
Answer and see the solution →Lithium (Li), sodium (Na), and potassium (K) are all Group 1 metals. Each loses its single outer electron in reactions. The number of protons in lithium is 3, in sodium is 11, and in potassium is 19.
Calculate the number of electron shells in an atom of potassium and explain how this relates to its reactivity compared to sodium.
Question 4
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 5
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 6
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 7
2 marks · Normal
Answer and see the solution →Explain why lithium reacts more slowly than sodium when added to water.
Question 8
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.