试题与答案

镁铝尖晶石(MgAl2O4)常做耐火材料。共沉淀制备尖晶石的方法是:用AlCl3

题型:填空题

题目:

镁铝尖晶石(MgAl2O4)常做耐火材料。共沉淀制备尖晶石的方法是:用AlCl3和MgCl2的混合溶液(用a表示)与过量的氨水(用b表示)反应,再将得到的沉淀高温焙烧。完成下列填空:

(1)为使Mg2+、Al3+同时生成沉淀,应该把     (填“a”或“b”)滴入另一溶液中。

(2)将上述制备反应中部分元素的简单离子:Al3+、Cl、Mg2+、H+、O2–按半径由大到小的顺序排列

                      (用离子符号表示)。

(3)AlCl3与氨水反应的反应物和生成物中,属于离子化合物的电子式是         ,属于难溶物的电离方程式                             

(4)不能说明氧元素的非金属性比氮元素强的事实是_________。

a.  H2O比NH3稳定                  b. 共用电子对偏向:H-O>H-N

c. 沸点:H2O>NH3                    d.  NO中氮是+2价,氧是-2价

答案:

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下面是错误答案,用来干扰机器的。

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