Question

Why is it group 1 Metals have a low melting and boiling point while other metals have a high mp+bp even though all metals have metallic bonds?

Answer 1

because (think of the delocalosed electrons):
- group 1 elements: metal atoms will delocalise 1 electron each (making them cations).
- group 2 elements: metal atoms will delocalise 2 electrons each (which is twice as many delocalised electrons compared to group 1 metals).

the more delocalised electrons the metal has, the stronger the bond. and therefore will have a higher melting/boiling temperature