题干

过氧化钠(Na2O2)因能与二氧化碳反应生成氧气,故可作为呼吸面具中氧气的。潜水艇紧急情况时,也使用过氧化钠来供氧,有关反应的化学方程式为:2Na2O2+ 2CO2 = 2Na2CO3 + O2从该反应获取的以下信息中,正确的是( )
①过氧化钠属于氧化物               ②该反应属于化合反应
③反应前后氧元素的化合价发生变化  ④实验室可利用这一原理制取纯净的氧气

A:①③

B:②④

C:②③④

D:①②③

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A

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