Should take off H from SH group, forming RS-Na+ salt. note: both S and O are group 16 elements. However, S is in the third row and O is in the second row. THe atomic size of S is bigger than that of O, thus S-H bond is weaker than O-H bond. The H in SH is more acidic than that in OH. the acidity of H: SH > OH > NH > CH Solution Should take off H from SH group, forming RS-Na+ salt. note: both S and O are group 16 elements. However, S is in the third row and O is in the second row. THe atomic size of S is bigger than that of O, thus S-H bond is weaker than O-H bond. The H in SH is more acidic than that in OH. the acidity of H: SH > OH > NH > CH.