下 * * 种物质中均含有氮元素，它们按下列顺序排列：①NH3；②N2；③NO；④X；⑤HNO3根据这种排列规律，X可能是 （ ）
A．N2O
B．NO2或NaNO2
C．N2O5
D．NaNO3
答案：B
题目分析：经分析，它们是按氮元素的化合价由低到高的顺序排列，①NH3中N的化合价为-3，②N2单质中N的化合价为0， ③NO中N的化合价为+2，⑤HNO3中N的化合价为+5，故物质④中N的化合价应在+2~+5之间，NO2中N的化合价为+4，NaNO2中N的化合价为+3，故选B
用所给词的正确形式填空。
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