( It ( ( is ( calculated ( as ( ( the sum ) ( of ( ( the mass ) ( of ( ( each ( constituent atom ) ) ( multiplied ( by ( ( the number ) ( of ( atoms ( of ( ( that element ) ( in ( the ( molecular formula ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (VBZ is) (VP (VBN calculated) (PP (IN as) (NP (NP (DT the) (NN sum)) (PP (IN of) (NP (NP (DT the) (NN mass)) (PP (IN of) (NP (NP (DT each) (JJ constituent) (NN atom)) (VP (VBN multiplied) (PP (IN by) (NP (NP (DT the) (NN number)) (PP (IN of) (NP (NP (NNS atoms)) (PP (IN of) (NP (NP (DT that) (NN element)) (PP (IN in) (NP (DT the) (JJ molecular) (NN formula)))))))))))))))))) (. .)))
It is calculated as the sum of the mass of each constituent atom multiplied by the number of atoms of that element in the molecular formula.
(ROOT (S (NP (NP (DT The) (NN sum)) (PP (IN of) (NP (NP (DT the) (NNS masses)) (PP (IN of) (NP (NP (DT the) (NNS atoms)) (PP (IN in) (NP (DT the) (NN formula)))))))) (VP (VBZ is) (VP (VBN referred) (PP (TO to) (NP (RB as) (JJ molecular) (NN mass))))) (. .)))