Question
SF6 is known but SCl6 is not known.
Solution
SF6 is known but SCl6 is not known Due to small size of S, six large Cl atoms cannot be accommodated around S atom, but small six F atoms can be easily accommodated around S atom to form SF6. Moreover, because of low electronegativity of Cl, it cannot easily cause promotion of electrons in S to form S(VI).
