13528
The two - electron reduction of O ( 2 ) by 1 , 1 ' - dibromoferrocene ( Br ( 2 ) Fc ) was catalyzed by Co ( II ) ( Ch ) , whereas virtually no reduction of O ( 2 ) occurred with Co ( II ) ( OEP ) .
 Chemical: O ( 2 ); Chemical: 1 , 1 ' - dibromoferrocene; Chemical: Br ( 2 ) Fc; Chemical: Co ( II ) ( Ch ); Chemical: O ( 2 ); Chemical: Co ( II ) ( OEP )
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: O ( 2 ); Chemical: 1 , 1 ' - dibromoferrocene; Chemical: Br ( 2 ) Fc; Chemical: Co ( II ) ( Ch ); Chemical: O ( 2 ); Chemical: Co ( II ) ( OEP )