题干

2003年诺贝尔化学奖授予了美国科学家Peter Agre和Roderick Mackinnon以表彰他们在“水通道”和“离子通道”的研究成就。Mackinnon教授的研究内容主要是Na+、K+体积很接近,但在生物体内呈现的差别却高达1万倍,他革命性的让科学家观测Na+、K+在进入离子通道前、通道中以及穿过通道后的状态,可为病人在“离子通道”中寻找具体的病因,并研制相应药物。下列关于钠、钾的说法正确的是

A:单质钠的密度比钾的密度小

B:钠和钾在空气中燃烧的产物都是过氧化物

C:钠和钾都是短周期元素

D:钠和钾的合金ω(K)=50%-80%在室温下呈液态

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D

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阅读理解

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