( Calorimeters ( ( are ( devices ( to ( measure ( heat ( released ( by ( a reaction ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNS Calorimeters)) (VP (VBP are) (NP (NNS devices) (S (VP (TO to) (VP (VB measure) (NP (NP (NN heat)) (VP (VBN released) (PP (IN by) (NP (DT a) (NN reaction)))))))))) (. .)))
Calorimeters are devices to measure heat released by a reaction.
(ROOT (S (NP (DT A) (NN calorimeter)) (VP (VBZ is) (NP (NP (DT a) (NN device)) (VP (VBN used) (S (VP (TO to) (VP (VB measure) (NP (NN temperature) (NNS changes)) (PP (IN during) (NP (NP (NN chemical) (NNS processes)) (VP (VBN called)))))))))) (. .)))