21688
We compare the rearrangement of the pure water surface by EE and FEE monolayers and the conformations of EE and FEE polar heads .
 Chemical: FEE; Chemical: FEE
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: FEE; Chemical: FEE