2008年9月25日,我国载人航天飞船“神州七号”发射成功。发射时从

2008925日,我国载人航天飞船神州七号发射成功。发射时从火箭尾部喷出的高温气体因含有NO2而呈红棕色

   1NO2中氮元素的化合价为           价。

   2NO2能与水发生化学反应,其化学方程式为:3 NO2 +H2O==HNO3 +X。根据质量守恒定律判断,X的化学式为            

   3HNO3中氧元素的质且分数是                     

 

答案

1+4  2NO   376.2%

 

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