问题 选择题

(2012•盐城)金属R与CuCl2溶液反应的化学方程式为:R+CuCl2=RCl2+Cu,则下列说法错误的是(  )

A.该反应是置换反应

B.金属R可能是铝

C.该反应是置换反应

D.金属R可能是铝

答案

答案:B

A、置换反应是单质与化合物生成单质与化合物,该反应符合置换反应的特征,故A说法正确;

B、该反应是金属R与氯化铜反应生成铜单质,根据金属的活动性顺序的应用可以知道该金属的活动性比铜强,可以是铝,但是铝在形成化合物时表现出的是化合价为+3价,而化学方程式生成的是RCl2,RCl2中R的化合价为+2价,故B说法错误;

C、根据B的解答可以知道该金属R的活动性比铜强,故C说法正确;

D、金属R为单质,根据化合价的原则可以知道其化合价为零,而RCl2中R的化合价为+2价,所以该反应前后R的化合价发生了改变,故D说法正确.

故选B.

单项选择题 B型题
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