( ( Two oxygens ) ( ( gives ( ( ( ( 12 ( valence electrons ) ) and ) ( 1 nitrogen ) ) ( ( gives 5 ) ( ( valence electrons ) ( for ( ( a total ) ( of ( 17 ( valence electrons ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (CD Two) (NNS oxygens)) (VP (VBZ gives) (SBAR (S (NP (NP (CD 12) (JJ valence) (NNS electrons)) (CC and) (NP (CD 1) (NN nitrogen))) (VP (VBZ gives) (NP (CD 5)) (NP (NP (JJ valence) (NNS electrons)) (PP (IN for) (NP (NP (DT a) (NN total)) (PP (IN of) (NP (CD 17) (JJ valence) (NNS electrons)))))))))) (. .)))
Two oxygens gives 12 valence electrons and 1 nitrogen gives 5 valence electrons for a total of 17 valence electrons.
(ROOT (S (NP (NNP Nitrogen)) (VP (VBZ has) (NP (CD 5) (JJ valence) (NNS electrons))) (. .)))