( ( As ( an example ) ) ( , ( ( ( ( 2,4-dichlorophenol ( with ( a pK ) ) ) a ) ( of 7.8 ) ) ( can ( ( exist ( either ( ( ( as ( the ( neutral compound ) ) ) or ) ( as ( ( the ( corresponding base ) ) ( with ( a ( net ( negative charge ) ) ) ) ) ) ) ) ) ( depending ( on ( the ( surrounding pH. ) ) ) ) ) ) ) ) )
(ROOT (S (PP (IN As) (NP (DT an) (NN example))) (, ,) (NP (NP (ADJP (JJ 2,4-dichlorophenol) (PP (IN with) (NP (DT a) (NN pK)))) (DT a)) (PP (IN of) (NP (CD 7.8)))) (VP (MD can) (VP (VB exist) (PP (CC either) (PP (IN as) (NP (DT the) (JJ neutral) (NN compound))) (CC or) (PP (IN as) (NP (NP (DT the) (JJ corresponding) (NN base)) (PP (IN with) (NP (DT a) (JJ net) (JJ negative) (NN charge)))))) (PP (VBG depending) (PP (IN on) (NP (DT the) (VBG surrounding) (NN pH.))))))))
As an example, 2,4-dichlorophenol with a pK a of 7.8 can exist either as the neutral compound or as the corresponding base with a net negative charge depending on the surrounding pH.
(ROOT (S (NP (JJ Iconic) (NNS compounds)) (VP (VBP have) (NP (DT a) (JJ net) (JJ neutral) (NN charge))) (. .)))