Question

Q1. Give reasons:-
1. As we move from lithium to potassium, atomic size increases down the group.
2. Ionic compounds have high melting and boiling point.
3. Elements of group1,2,3 generally form cations.

Answer 1

AnswEr :

1) As we move from lithium to potassium or simply moving down in a group size increses, it is because of addition of shells.

2) Ionic compounds have high melting and boiling point because there bonds are tightly packed. and we've to do more work to break bonds between them. So, generally ionic compounds have high melting as well as high boiling point.

3) Elements of group 1,2,3 are generally cations because they have additional electrons in their outermost shell. So, they donate electrons to electronegative atoms therefore a charge is developed on them. This is reason why they are cations.