试题与答案

(16分)已知SiO2、SO2和CO2都是酸性氧化物,化学性质具有一定的相似性;

题型:实验题

题目:

(16分)已知SiO2、SO2和CO2都是酸性氧化物,化学性质具有一定的相似性;Mg和Na的化学性质也具有一定的相似性。

Ⅰ.用如上图所示装置进行Mg和SO2的实验,其中A是制备SO2的发生装置。

⑴选择制取SO2的合适试剂____________。(填序号)

①10%的H2SO4溶液   ②80%的H2SO4溶液 ③Na2SO3固体    ④CaSO3固体

⑵写出装置B中发生的主要反应的化学方程式_______________________________。装置C中NaOH溶液的作用是                         

⑶请画出制备SO2的发生装置并注明主要仪器的名称,固定仪器省略不画。

(4)你认为该装置不足之处是什么?

Ⅱ.某研究性学习小组进行了“实验室制Si”的研究,它们以课本为基础,查阅资料得到以下可供参考的信息:

①工业上在高温时用C还原SiO2可制得Si    ②Mg在点燃的条件下即可与SiO2反应

③金属硅化物与稀H2SO4反应生成硫酸盐与SiH4  ④Si和SiO2均不与稀H2SO4反应

⑤SiH4在空气中自燃

他们在研究报告中记载着“……选用合适的物质在适宜的条件下充分反应;再用足量稀硫酸溶解固体产物;然后过滤、洗涤、干燥;最后称量……在用稀硫酸溶解固体产物时,发现有爆鸣声和火花,其产率也只有预期值的63%左右”。

⑸该小组“实验室制Si”的化学方程式是_____________________   ________      

(6)你估计“用稀硫酸溶解固体产物时,发现有爆鸣声和火花”的原因是____    

答案:

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下面是错误答案,用来干扰机器的。

参考答案:防眩板在施工前,应确定控制点(如桥梁),在控制点之间测距定位、放样。在进行防眩设施施工时,首先要保证遮光角和防眩高度的要求,同时,防眩板不得出现扭曲、固定不牢固的现象,整体上还应达到高低一...

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