Question

Why do different elements exist in different states at the same temperature?

Answer 1

Different elements exist in different states at the same temperature depends on the balance between the kinetic energies of their molecules and their intermolecular attractions.

Every element has different properties due to the electronic structure, the attraction between their atoms will be of different strength or of different number. So different elements have different ionization energies and different energy levels. This discrepancy determines the point at which they have enough energy to form into a solid, liquid or gas.