试题与答案

一定量的液态化合物XY2,在一定量O2中恰好完全反应:XY2(l)+3O2(g)

题型:计算题

题目:

一定量的液态化合物XY2,在一定量O2中恰好完全反应:XY2(l)+3O2(g)==XO2(g)+2YO2(g),其中l、g分别表示物质为液体、气体。冷却后,在标准状况下,测得生成物的体积为672mL,密度为2.56 g·L-1,写出(1)和(2)的简要计算过程。

(1)反应前O2的体积为______________。

(2)化合物XY2的摩尔质量是________。

(3)在XY2分子中,X、Y两元素的质量之比为3∶16,则X、Y两元素分别为______和______(写元素名称)。

答案:

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