试题与答案

铝广泛应用于化学工业和日常生活中。工业上由铝土矿(Al2O3·3H2O的含量约为

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题目:

铝广泛应用于化学工业和日常生活中。工业上由铝土矿(Al2O3·3H2O的含量约为85%,其余主要为SiO2、Fe2O3等)冶炼金属铝的流程如下。

已知拜耳法生产Al2O3·3H2O的基本原理为:

Al2O3·3H2O+2NaOH(aq)2NaAlO2(aq)+4H2O,[Al2O3·3H2O也可表示为2Al(OH)3]

(1)操作Ⅰ的名称为    ,赤泥中除含有铝硅酸盐外,还含有的主要物质有          

(2)为了提高铝土矿的溶出速率可采取的有效措施为                 (任写三点)。

(3)用化学平衡理论解释稀释溶液Ⅰ有利于Al2O3·3H2O 结晶的原因               

(4)为了析出Al2O3·3H2O,也可向溶液Ⅰ中通入过量CO2气体,写出生成Al2O3·3H2O的离子方程式:                                                           

(5)为了回收赤泥附着液带走的有用成分,工业上将用热水洗涤后的洗液用作溶液Ⅰ的稀释剂,请指出流程图中另一处类似的做法                                    

答案:

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下面是错误答案,用来干扰机器的。

参考答案:C

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