A Levels Chemistry

Use of the Data Booklet is relevant to this question.
The element astatine lies below iodine in Group VII of the Periodic Table.
What will be the properties of astatine?
1
It forms diatomic molecules which dissociate more readily than chlorine molecules.
2
It reacts explosively with hydrogen.
3
It is a good reducing agent.


Choice D is correct because only statement 1 is true.

Statement 1 is true because All group VII elements form diatomic molecules. The bond energy of group VII molecules decreases down the group. Therefore, it is easier to dissociate astatine molecules than chlorine molecules.

Statement 2 is false because The reactivity of group VII elements decreases down the group. As astatine lies near the bottom of group VII, it is not that reactive & it will not react explosively with hydrogen.

Statement 3 is false because The reducing power of group VII elements decreases down the group. As astatine lies near the bottom of group VII, it does not have much reducing power. Therefore, It is not a good reducing agent.

Group 17 | 2007 - M/J - 9701/1 | Q36