22963
As the oxygen extraction reaction is one order of magnitude slower than physisorption , it lies hidden underneath of the faster physisorption processes in the mass spectrum but is revealed by the elimination of physisorption through the post heating .
 Chemical: oxygen
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: oxygen