试题与答案

把MgCl2、AlCl3两种固体组成的混合物溶于足量的水后,在所得溶液中逐滴加入

题型:计算题

题目:

把MgCl2、AlCl3两种固体组成的混合物溶于足量的水后,在所得溶液中逐滴加入10%的NaOH溶液,加入NaOH溶液的质量和生成沉淀的质量如下图所示。已知:NaOH与AlCl3反应时,先使AlCl3全部转化为不溶于水的Al(OH)3,然后Al(OH)3还能继续与过量的NaOH发生如下反应:Al(OH)3+NaOH====NaAlO2+2H2O,其中NaAlO2 是可溶于水的物质,试回答:

(1)A点的沉淀物的化学式有           ; B点的沉淀物的化学式是          

(2)原混合物中MgCl2、AlCl3的质量各为多少克?

答案:

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