The melting and boiling points of metals decrease on going down the group.
Example: Observe the trend in group 1 elements given in the following table:
From the above table, it is clear that m.p. and b.p. decrease from Li to K.
The melting and boiling points of non-metals increase on going down the group.
Example: Observe the trend in Group 17 elements given in the following table:
From the above table, it is clear that m.p. and b.p. increase from F to I.
