5919
The acidity of the backbone amides , as reflected in hydrogen exchange rates , is exquisitely sensitive to the surrounding charge and dielectric volume distribution .
 Chemical: amides; Chemical: hydrogen
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: amides; Chemical: hydrogen