The fluoride SF₄ is used in the pharmaceutical industry to synthesize fluorocarbons, some of which are used as anesthetics. Write the Lewis structure of sulfur tetrafluoride and give the number of electrons in the expanded valence shell.

ANTICIPATE Sulfur, in Group 16, has six valence electrons; if each fluorine atom provides one electron for the bond it forms, you should expect there to be 4 + 6 = 10 electrons around the S atom.

PLAN Elements in Period 3 and later periods can expand their valence shells to accept additional electrons. After assigning all the valence electrons to bonds and lone pairs to give each atom an octet, assign any remaining electrons to the central atom as lone pairs.