( ( The ( pH scale ) ) ( ( is ( used ( to ( measure ( ( ( the degree ) ( of ( ( acidity or ) alkalinity ) ) ) ( of ( a solution ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN pH) (NN scale)) (VP (VBZ is) (VP (VBN used) (S (VP (TO to) (VP (VB measure) (NP (NP (DT the) (NN degree)) (PP (IN of) (NP (NN acidity) (CC or) (NN alkalinity))) (PP (IN of) (NP (DT a) (NN solution))))))))) (. .)))
The pH scale is used to measure the degree of acidity or alkalinity of a solution.
(ROOT (S (NP (NP (DT The) (NN acidity)) (PP (IN of) (NP (DT a) (NN solution)))) (VP (VBZ is) (ADVP (RB typically)) (VP (VBN assessed) (ADVP (RB experimentally)) (PP (IN by) (NP (NP (NN measurement)) (PP (IN of) (NP (PRP$ its) (NN ph.)))))))))