19801
Acoustic properties of three ( 1 - ethyl - , 1 - butyl - , and 1 - octyl - ) 1 - alkyl - 3 - methylimidazolium bis [ ( trifluoromethyl ) sulfonyl ] imide room - temperature ionic liquids are reported and discussed .
 Chemical: 1 - ethyl; Chemical: 1 - butyl; Chemical: 1 - octyl; Chemical: 1 - alkyl - 3 - methylimidazolium bis [ ( trifluoromethyl ) sulfonyl ] imide
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: 1 - ethyl; Chemical: 1 - butyl; Chemical: 1 - octyl; Chemical: 1 - alkyl - 3 - methylimidazolium bis [ ( trifluoromethyl ) sulfonyl ] imide