【題目】有兩個集氣瓶，分別充滿空氣和氮氣，試用簡單的方法加以鑒別。

________________________________________________________________________。

【答案】用燃著的木條分別伸入兩個集氣瓶中，木條繼續(xù)燃燒的是空氣，木條立即熄滅的是氮氣

【解析】

試題分析：氮氣不支持燃燒，而空氣中含有支持燃燒的氧氣，所以可以：用燃著的木條分別伸入兩個集氣瓶中，木條繼續(xù)燃燒的是空氣，木條立即熄滅的是氮氣。

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