In the second reaction the sulfate ( +6 oxidation state ) oxidizes the sulfide ( -2 oxidation state ) to sulfur dioxide ( +4 oxidation state ) , while it is being reduced to sulfur dioxide itself ( +4 oxidation state ) .
ADP DET ADJ NOUN DET NOUN ( PROPN NOUN NOUN ) VERB DET NOUN ( INTJ NOUN NOUN ) PART NOUN NOUN ( NOUN NOUN NOUN ) , SCONJ PRON AUX AUX VERB ADP NOUN NOUN PRON ( NOUN NOUN NOUN ) .