( ( and ( ( ( ( 2 -RRB- ) ( ( the concentration ) ( of substance ) ) ) ( -LRB- ( ( ( number ( of ( ( molecules or ) moles ) ) ) ( per ( unit volume ) ) ) -RRB- ) ) ) ( in ( the solution ) ) ) ) . )
(ROOT (S (VP (VB and) (NP (NP (NP (LST (LS 2) (-RRB- -RRB-)) (NP (DT the) (NN concentration)) (PP (IN of) (NP (NN substance)))) (PRN (-LRB- -LRB-) (NP (NP (NN number)) (PP (IN of) (NP (NNS molecules) (CC or) (NNS moles))) (PP (IN per) (NP (NN unit) (NN volume)))) (-RRB- -RRB-))) (PP (IN in) (NP (DT the) (NN solution))))) (. .)))
and 2) the concentration of substance (number of molecules or moles per unit volume) in the solution.
(ROOT (S (NP (NP (DT The) (NN number)) (PP (IN of) (NP (NP (NNS particles)) (PP (IN of) (NP (NP (DT a) (NN substance)) (PP (IN in) (NP (DT a) (VBN given) (NN volume)))))))) (VP (VBZ is) (VP (VBN known) (PP (IN as) (NP (DT the) (NN concentration))))) (. .)))