题型:选择题 Most of the factories under___________ have been designed by Chinese engineers.A.controlB.constructionC.contributionD. conclusion 查看答案
题型:选择题 NA代表阿伏加德罗常数的值,下列说法正确的是 A.5.6 g 铁在足量氯气中燃烧,电子转移0.2 NA个B.标准状况下,2.24 L水中含有0.1 NA个水分子C.1.12 L氯气中含有0.1 NA个氯原子D.0.1molNa2O2与足量的CO2反应转移的电子数为0.1NA 查看答案