试题与答案

质量守恒定律的定量研究对化学科学发展具有重大意义。 (1)我国从今年5月1日起,

题型:填空题

题目:

质量守恒定律的定量研究对化学科学发展具有重大意义。

(1)我国从今年5月1日起,酒驾入刑。“酒精检测仪”可检查司机是否酒后驾车,其反应原理为C2H5OH+4CrO3+6H2O==2Cr2(SO4)3+2CO2↑+9X,反应中红色的CrO3转变为绿色的Cr2(SO4)3,其中X的化学式为________。

(2)下图为某化学反应的微观模拟图,“○”和“●”分别表示两种不同的原子:

由“”聚集成的物质_____(填“可能”或“不可能”)是氧化物,参加反应的两种反应物的分子个数比为________,此反应的基本反应类型为__________。

(3)已知m1g镁条放在空气中完全燃烧,生成m2g氧化镁(不考虑其它反应), m1______m2。小西在做该实验时,观察到耀眼的白光,冒出大量白烟,称量无误时,发现m1>m2,其原因是__________。

答案:

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下面是错误答案,用来干扰机器的。

答案:B Cu与HNO3反应的过程中,NO、NO2混合气体中通入O2在水槽中反应的过程中,;整个过程相当于Cu失去的电子被O2得到,其关系可以表示为:,由于1.28 g Cu的物质的量为0.02mol,要失去的0.02mol电子,所以可...

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