28776
A solid phase extraction method for enrichment - separation and the determination of cobalt ( Co ( 2 + ) ) , copper ( Cu ( 2 + ) ) , nickel ( Ni ( 2 + ) ) , zinc ( Zn ( 2 + ) ) and lead ( Pb ( 2 + ) ) ions in real samples has been proposed .
 Chemical: cobalt; Chemical: Co ( 2 + ); Chemical: copper; Chemical: Cu ( 2 + ); Chemical: nickel; Chemical: Ni ( 2 + ); Chemical: zinc; Chemical: Zn ( 2 + ); Chemical: Pb ( 2 + )
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: cobalt; Chemical: Co ( 2 + ); Chemical: copper; Chemical: Cu ( 2 + ); Chemical: nickel; Chemical: Ni ( 2 + ); Chemical: zinc; Chemical: Zn ( 2 + ); Chemical: Pb ( 2 + )