单选题在制药时，为从溶液中提取抗菌素，要用加热的方法使水沸腾而除去水分，但抗生素不能在超过80℃的条件下提取，应采用的办法是（）。A增加容器内的气压，使水的沸点低于80℃B降低容器内的气压，使水的沸点低于80℃C缩短加热沸腾的时间D用微火加热使其沸腾
单选题
在制药时，为从溶液中提取抗菌素，要用加热的方法使水沸腾而除去水分，但抗生素不能在超过80℃的条件下提取，应采用的办法是（）。
A
增加容器内的气压，使水的沸点低于80℃
B
降低容器内的气压，使水的沸点低于80℃
C
缩短加热沸腾的时间
D
用微火加热使其沸腾
参考解析
解析：
此题要求降低水的沸点才能提取抗菌素，根据沸点和气压的关系，气压越大，沸点越高，气压越小，沸点越低，所以答案为B。
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