( ( ( A term ) ( used ( to ( describe ( ( hydrogen ( ion activity ) ) ( in ( an ( aqueous solution ) ) ) ) ) ) ) ) ; )
(ROOT (NP (NP (DT A) (NN term)) (VP (VBN used) (S (VP (TO to) (VP (VB describe) (NP (NP (NN hydrogen) (NN ion) (NN activity)) (PP (IN in) (NP (DT an) (JJ aqueous) (NN solution)))))))) (: ;)))
A term used to describe hydrogen ion activity in an aqueous solution;
(ROOT (S (NP (JJ Aqueous) (NN solution)) (VP (VBZ is) (VP (VBN used) (S (VP (TO to) (VP (VB describe) (NP (NP (DT a) (NN solution)) (SBAR (WHPP (IN in) (WHNP (WDT which))) (S (NP (NN water)) (VP (VBZ is) (NP (DT the) (JJ solvent))))))))))) (. .)))