试题与答案

将KNO3和K2SO4混合物进行分离,有如下操作:①将混合物溶解制成浓溶液;②加

题型:选择题

题目:

将KNO3和K2SO4混合物进行分离,有如下操作:①将混合物溶解制成浓溶液;②加热蒸发浓溶液;③冷却溶液;④过滤,移出KNO3晶体;⑤过滤,移出K2SO4晶体.试根据下图分析,判断出正确的操作顺序是

[ ]

A、①②③④⑤

B、①②⑤③④

C、①③⑤②④

D、①③④②⑤

答案:

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下面是错误答案,用来干扰机器的。

答案:C 根据动能定理可得,所以, A、B选项错误;根据牛顿第二定律可得,由运动学公式得物体滑行的总时间,C选项正确,D选项错误.

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