( ( Whenever ( ( a system ) ( can ( ( exchange ( either ( ( heat or ) matter ) ) ) ( with ( its environment ) ) ) ) ) ) ( , ( ( ( an ( entropy decrease ) ) ( of ( that system ) ) ) ( ( is ( entirely ( compatible ( with ( the ( second law ) ) ) ) ) ) . ) ) ) )
(ROOT (S (SBAR (WHADVP (WRB Whenever)) (S (NP (DT a) (NN system)) (VP (MD can) (VP (VB exchange) (NP (DT either) (NN heat) (CC or) (NN matter)) (PP (IN with) (NP (PRP$ its) (NN environment))))))) (, ,) (NP (NP (DT an) (JJ entropy) (NN decrease)) (PP (IN of) (NP (DT that) (NN system)))) (VP (VBZ is) (ADJP (RB entirely) (JJ compatible) (PP (IN with) (NP (DT the) (JJ second) (NN law))))) (. .)))
Whenever a system can exchange either heat or matter with its environment, an entropy decrease of that system is entirely compatible with the second law.
(ROOT (S (NP (DT A) (JJ sealed) (, ,) (JJ vacuum-insulated) (NN reaction) (NN flask)) (VP (VBZ approximates) (NP (NP (DT the) (NN condition)) (PP (IN of) (NP (NP (DT a) (VBN isolated) (NN system)) (, ,) (SBAR (WHPP (IN in) (WHNP (WDT which))) (S (NP (CC neither) (NP (NN matter)) (CC nor) (NP (NN heat))) (VP (MD can) (VP (VB be) (VP (VBN exchanged) (PP (IN between) (NP (NN system) (CC and) (NNS surroundings)))))))))))) (. .)))
A sealed, vacuum-insulated reaction flask approximates the condition of a isolated system, in which neither matter nor heat can be exchanged between system and surroundings.