As a solid element melts, the atoms become and they have attraction for one another.

As a solid element melts, the atoms become more separated and they have less attraction for one another.
When a solid element starts melting, it means that it is using up a lot of energy it has stored. And when there is a lot of energy being used up, its particles are vibrating fast, and becoming more and more separated. So obviously, if these atoms are far from each other, they aren't going to attract.

Tolerance to high levels of salinity