Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
Explaining the trend in the reactivity of the halogens
19 practice questions
Practice questions
1–8 of 8 · Normal
Question 1
2 marks · Normal
Answer and see the solution →State two trends that occur when you go down Group 7 (the halogens) in the Periodic Table.
Question 2
4 marks · Normal
Answer and see the solution →This question is about electrons and halogen reactivity.
(a)[1 mark]State the charge on the ion formed when a chlorine atom gains an electron.
(b)[3 marks]Explain, in terms of electron arrangement, why chlorine is more reactive than bromine.
Question 3
3 marks · Normal
Answer and see the solution →Explain why astatine is less reactive than bromine, in terms of atomic structure and electronic configuration.
Question 4
4 marks · Normal
Answer and see the solution →The table shows some properties of Group 7 elements.
Element Colour at room temperature State at room temperature Melting point (°C) Chlorine Green Gas -101 Bromine Red-brown Liquid -7 Iodine Dark grey Solid 114 (a)[2 marks]Predict the appearance and physical state of astatine at room temperature.
(b)[2 marks]Suggest a melting point for astatine, based on the trend in the table.
Question 5
1 mark · Normal
Answer and check →Which statement best explains why chlorine is more reactive than bromine?
- A.Chlorine has a higher nuclear charge than bromine.
- B.Chlorine has a smaller atomic radius, so its outer electrons are more strongly attracted to the nucleus.
- C.Chlorine forms positive ions more easily than bromine.
- D.Chlorine has more energy levels than bromine.
Question 6
2 marks · Normal
Answer and see the solution →State what you would observe if chlorine water is added to a solution of sodium iodide. Explain your answer.
Question 7
4 marks · Normal
Answer and see the solution →This question is about how halogens react by gaining electrons.
(a)[1 mark]Describe what happens to a bromine atom when it reacts to form a bromide ion.
(b)[3 marks]Explain, using electron arrangement, why it is easier for chlorine to form an ion than bromine.
Question 8
3 marks · Normal
Answer and see the solution →Iodine (I2) is a solid at room temperature, and its melting point is 114 °C. Its colour as a solid is purple-black. Astatine (At) is the element below iodine in Group 7 and has not been isolated, but its properties can be predicted from group trends.
Predict the following properties of astatine (At2) based on your knowledge of halogen group trends:
(a)[1 mark]State the physical state (solid, liquid or gas) in which astatine would exist at room temperature.
(b)[1 mark]Estimate whether the melting point of astatine would be higher or lower than that of iodine. Explain your answer.
(c)[1 mark]State and explain what colour (compared to iodine) you would expect astatine to be as a solid.