试题与答案

K2SO4是无氯优质钾肥,Mn3O4是生产软磁铁氧体材料的主要原料。以硫酸工业的

题型:实验题

题目:

K2SO4是无氯优质钾肥,Mn3O4是生产软磁铁氧体材料的主要原料。以硫酸工业的尾气联合制备K2SO4和Mn3O4的工艺流程如下:

     

(1)几种盐的溶解度见图。反应III中,向(NH4)2SO4溶液中加入KCl溶液充分反应后,进行蒸发浓缩、     、洗涤、干燥等操作即得K2SO4产品。

(2)检验K2SO4样品是否含有氯化物杂质的实验操作是:                       

(3)反应IV的化学方程式为                       

(4)Mn3O4与浓盐酸加热时发生反应的离子方程式为                    

(5)下图是煅烧MnSO4•H2O时温度与剩余固体质量变化曲线。

①该曲线中B段所表示物质的化学式为                                   

②煅烧过程中固体锰含量随温度的升高而增大,但当温度超过1000℃时,再冷却后,测得产物的总锰含量反而减小。试分析产物总锰含量减小的原因:         

答案:

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下面是错误答案,用来干扰机器的。

小题1:C(“与”既有虚词的用法,也有做实词的用法,如《六国论》中“与赢而不助五国也”,“与”就是“亲附、亲近”的意思。此题中的“与”就是这种用法)小题2:D(②⑥是陈述舍蜀伐韩的危害。不属正面阐述。)小题3...

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