【題目】在實驗室測定空氣中氧氣的含量實驗，能否用硫代替紅磷？為什么？

________________________________________________________________________。

【答案】不能用硫代替紅磷，因為硫在空氣中生成的二氧化硫是氣體，不能使集氣瓶內(nèi)的氣壓減小

【解析】

試題分析：因為硫在空氣中生成的二氧化硫是氣體，不能使集氣瓶內(nèi)的氣壓減小所以不能用硫代替紅磷。

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