( ( The ( yellow one ) ) ( ( measures ( ( the reactivity ) ( of ( ( the chemical ) ( with ( other chemicals ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (JJ yellow) (NN one)) (VP (VBZ measures) (NP (NP (DT the) (NN reactivity)) (PP (IN of) (NP (NP (DT the) (NN chemical)) (PP (IN with) (NP (JJ other) (NNS chemicals))))))) (. .)))
The yellow one measures the reactivity of the chemical with other chemicals.
(ROOT (S (NP (NP (DT The) (NN ability)) (PP (IN of) (NP (NN matter) (S (VP (TO to) (VP (VB combine) (ADVP (RB chemically)) (PP (IN with) (NP (JJ other) (NNS substances))))))))) (VP (VBZ is) (VP (VBN known) (PP (IN as) (NP (NN reactivity))))) (. .)))