27200
Methane is exothermically dehydrogenated by several 5d metal ions to form [ M , C , 2H ] + and H2 .
 Methane, C, 2H, H2
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 Methane, C, 2H, H2