Question

Which statement best describes the polarity of the molecule Sil4

a. it is polar, because the bond polarities add together in a tetrahedral molecule

b. It is non-polar, because the bond polarities cancel each other out in a tetrahedral molecule

c. it is non-polar, because the bonds between silicon (si) and iodine (I) are not polar

d. it is polar, because the bond polarities add together in a trigonal-planar molecule

Answer 1

b. It is nonpolar, because the bond polarities cancel each other out in a tetrahedral molecule.

The structure of SiI4 is Si bonded to four I atoms, with no lone pairs on Si, so the structure is tetrahedral and the bond polarities cancel due to symmetry.