( ( ( Very accurate ) ( mass measurements ) ) ( ( ( can also ) ( be ( used ( to ( determine ( ( the ( elemental ( formulas ( or ( elemental composition ) ) ) ) ) ( of compounds ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (ADJP (RB Very) (JJ accurate)) (NN mass) (NNS measurements)) (VP (MD can) (ADVP (RB also)) (VP (VB be) (VP (VBN used) (S (VP (TO to) (VP (VB determine) (NP (NP (DT the) (JJ elemental) (NNS formulas) (CC or) (NN elemental) (NN composition)) (PP (IN of) (NP (NNS compounds)))))))))) (. .)))
Very accurate mass measurements can also be used to determine the elemental formulas or elemental composition of compounds.
(ROOT (S (NP (DT The) (NN term) (NN percent) (NN composition)) (VP (VBZ means) (NP (DT the) (NN percentage)) (PP (IN by) (NP (NP (NN mass)) (PP (IN of) (NP (NP (DT each) (NN element)) (PP (IN in) (NP (DT a) (NN compound)))))))) (. .)))