The change of state that has been given in the question is called sublimation. It is actually the process in which a solid gets directly converted to gas without changing into liquid. I hope that this is the answer that you were looking for and the answer has actually come to your desired help.
Most elements on group 18 are the Noble Gases. They already have a complete last level with 8 electrones. Actually they can form compounds but only on the lab and they will not even last half a second.
The Ti 2+ ions is represented by electron configuration (Ar)3d2. Titanium is in atomic number 22 and its electronic configuration is (Ar)3d2 4s2. Titanium loss two electron that is 4s2 electrons hence the electronic configuration ( Ar)3d2. 4s2 is the valence electron hence it the one which is lost to form Ti2+
Heat needed=mcθ
=7×0.031×(42-17)
=5.425cal
