4571
The linear model was significantly fitted to the relationship between { Cu ( 2 + ) } / Cu ( root ) and { Mg ( 2 + ) } .
 Chemical: Cu ( 2 + ); Chemical: Cu; Chemical: Mg ( 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: Cu ( 2 + ); Chemical: Cu; Chemical: Mg ( 2 + )