posted by Bill .
What has the higher normal melting point: CHI3 or CHF3?
The answer in the book is CHI3. So I'm assuming the answer is CHI3 because Iodine is the bigger and will form larger london dispersion forces, but isn't a stronger dipole moment formed in CHF3 because fluorine is more electronegative than carbon and forms a polar molecule?
Yes, CHF3 is more polar but the size trumps that. I looked up the boiling points of
CHF3 is about -82 C.
CHCl3 is about 61
CHBr3 is about 149
CHI3 is about 218