Why is #F_2, Cl_2# gaseous room temperature while #I_2# is a solid? Please give an answer relating to bond strength.

1 Answer
Sep 29, 2017

Well, the #I-I# bonds are MUCH weaker than those of #F-F#, and #Cl-Cl#.

Explanation:

However the physical state of the element is the result of #"intermolecular bonding"#, the bonds between molecules, rather than #"intramolecular bonding"#, the bonds within a molecule. Please note the distinction.

Because, iodine is a larger, more polarizable molecule, with a large electron cloud, the molecule has a greater degree of #"intermolecular bonding"#, arising from dispersion forces, and is thus a room temperature solid.