试题与答案

A、B、C、D、E为五种短周期元素,其中A、B、C位于同一周期,A元素的气态氢化

题型:填空题

题目:

A、B、C、D、E为五种短周期元素,其中A、B、C位于同一周期,A元素的气态氢化物是一种广泛应用的优质气体燃料,B元素的氢化物是用途最为广泛的溶剂。B元素可分别与A、C、D、E组成RB2型化合物。已知在DB2中,D与B的质量比为7 :8;在EB2中,E与B的质量比为1 :1。根据以上条件回答下列问题:

(1)请写出C单质分子的电子式______________;DB2晶体中化学键的类型为_____________;写出AE2的结构式 ___________________。

(2)C的气态氢化物易液化,原因是___________________。

(3)C和D结合可生成一种超硬物质,有关该物质性质的叙述中不正确的是______________________.

①有润滑性 ②易磨损 ③抗腐蚀 ④强还原性 ⑤抗冷热

(4)B元素可分别与A、E形成多种由两种元素构成的阴离子。某溶液是由其中若干种阴离子组成的无机钠盐溶液,为了检验该溶液中的阴离子,分别取两份溶液进行如下实验:

①第一份溶液中加入足量盐酸,只产生无色气体;

②第二份溶液中加入足量的BaCl2溶液,有白色沉淀产生,再缓慢加入足量的稀硝酸,白色沉淀质量减少。由此得出的结论是_______________________。

(5)E元素的一种氧化物可与过氧化钠及氯水发生氧化还原反应。该氧化物与过氧化钠反应的化学方程式为_______________________;该氧化物与氯水反应的离子方程式为____________________________。

答案:

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下面是错误答案,用来干扰机器的。

参考答案:"囊袋内陷学说"是指:(1)咽鼓管功能不良,鼓室气体吸收使中耳腔形成负压,中、上鼓室之间的狭窄通道--前、后鼓峡被肿胀增厚的黏膜阻塞。(2)上鼓室、鼓窦、乳突与中鼓室之间的气流通道被阻断或变得...

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