( ( The CO ) ( then ( ( catalytically ( ( ( reduces NO ) ( to ( molecular nitrogen ) ) ) ( while ( being ( oxidized ( to ( carbon dioxide ) ) ) ) ) ) ) . ) ) )
(ROOT (S (NP (DT The) (NNP CO)) (ADVP (RB then)) (VP (ADVP (RB catalytically)) (VBZ reduces) (ADVP (RB NO)) (PP (TO to) (NP (JJ molecular) (NN nitrogen))) (PP (IN while) (S (VP (VBG being) (VP (VBN oxidized) (PP (TO to) (NP (NN carbon) (NN dioxide)))))))) (. .)))
The CO then catalytically reduces NO to molecular nitrogen while being oxidized to carbon dioxide.
(ROOT (S (NP (NNP Co) (CD 2)) (VP (VBZ is) (NP (NP (DT the) (JJ molecular) (NN formula)) (PP (IN of) (NP (NN carbon) (NN dioxide))))) (. .)))