试题与答案

沼气是一种廉价的能源。农村富有秸秆、杂草等废弃物,它们经微生物发酵之后,便可以产

题型:计算题

题目:

沼气是一种廉价的能源。农村富有秸秆、杂草等废弃物,它们经微生物发酵之后,便可以产生沼气,可以用来点火做饭。

(1)煤的主要成分是碳,写出煤和沼气中的主要成分燃烧过程的化学方程式_____________________、

_____________________;并指出哪一种燃料对环境的污染小?_____________________。

(2)我国农村大约有700万个沼气发生池,如果每个沼气池平均每天产生2立方米的沼气(主要是甲烷),1mol甲烷完全燃烧能放出890kJ的热量,计算每天可节约燃烧值为3.36×107J·kg-1的标准煤多少千克?

答案:

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参考答案:B

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