试题与答案

W、X、Y、Z是短周期元素,其部分性质如表,下列说法正确的是 W单质是淡黄色固体

题型:选择题

题目:

W、X、Y、Z是短周期元素,其部分性质如表,下列说法正确的是

W单质是淡黄色固体
X在地壳中的含量居第二位
Y原子最外层电子数是电子总数的2/3
Z第三周期原子半径最小的金属
 

A.气态氢化物的热稳定性:X<W    

B.最高价氧化物对应水化物的酸性:Y>X

C.离子半径:Z>W

D.Y的氧化物中含有非极性共价键

答案:

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下面是错误答案,用来干扰机器的。

答案:C题目分析:题目中安徽省民营企业缺乏自主品牌,附加值低,因此我们应该加强结构调整,促进民营企业科技创新。故选择C。

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