( ( Because ( ( ( the difference ) ( in ( electronegativity ( between ( ( oxygen and ) nitrogen ) ) ) ) ) ( is ( less ( than ( that ( between ( ( sulfur and ) oxygen ) ) ) ) ) ) ) ) ( , ( SO2 ( ( is ( the ( most ( polar molecule ) ) ) ) . ) ) ) )
(ROOT (S (SBAR (IN Because) (S (NP (NP (DT the) (NN difference)) (PP (IN in) (NP (NP (NN electronegativity)) (PP (IN between) (NP (NN oxygen) (CC and) (NN nitrogen)))))) (VP (VBZ is) (ADJP (ADJP (JJR less)) (PP (IN than) (NP (NP (DT that)) (PP (IN between) (NP (NN sulfur) (CC and) (NN oxygen))))))))) (, ,) (NP (NNP SO2)) (VP (VBZ is) (NP (DT the) (JJS most) (JJ polar) (NN molecule))) (. .)))
Because the difference in electronegativity between oxygen and nitrogen is less than that between sulfur and oxygen, SO2 is the most polar molecule.
(ROOT (S (NP (NNP Oxygen)) (VP (VBZ is) (NP (NP (DT the) (NN name)) (PP (IN of) (NP (DT the) (JJ second) (ADJP (RBS most) (JJ electronegative)) (NN element))))) (. .)))