Why is the boiling point and melting point of 15th group and 16th group has an exception?
We know that as molecular mass increases boiling point and melting point also increase. So, down the group 15 and 16, as molecular mass increases, melting and boiling point should also increase but melting and boiling point of antimony is more than that of bismuth. (even though molecular mass of bismuth is more)
Similarly, melting and boiling point of tellurium is higher than polonium. Why is it so?