275413
Down the group 16 column , the bond strength becomes increasingly weaker ( 234 kJ / mol for the C – Se bond and 272 kJ/mol for the C – S bond ) and the bond length s longer ( C – Se 198 pm , C – S 181 pm and C – O 141 pm ) .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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