试题与答案

以富含硫酸亚铁的工业废液为原料生产氧化铁的工艺如下(部分操作和条件略): Ⅰ.从

题型:填空题

题目:

以富含硫酸亚铁的工业废液为原料生产氧化铁的工艺如下(部分操作和条件略):

Ⅰ.从废液中提纯并结晶出FeSO4·7H2O。

Ⅱ.将FeSO4·7H2O配制成溶液。

Ⅲ.FeSO4溶液与稍过量的NH4HCO3溶液混合,得到含FeCO3的浊液。

Ⅳ.将浊液过滤,用90℃热水洗涤沉淀,干燥后得到FeCO3固体。

ⅴ.煅烧FeCO3,得到Fe2O3固体。

已知:NH4HCO3在热水中分解。

(1)Ⅰ中,加足量的铁屑除去废液中的Fe3+,该反应的离子方程式是______________________。

(2)Ⅱ中,需加一定量硫酸。运用化学平衡原理简述硫酸的作用_________________。

(3)Ⅲ中,生成FeCO3的离子方程式是_________________。若FeCO3浊液长时间暴露在空气中,会有部分固体表面变为红褐色,该变化的化学方程式是_________________。

(4)IV中,通过检验SO42-来判断沉淀是否洗涤干净。检验SO42-的操作是_________________。

(5)已知煅烧FeCO3的化学方程式是4FeCO3+O22Fe2O3+4CO2。现煅烧464.0 kg 的FeCO3,得到

316.8 kg产品。若产品中杂质只有FeO,则该产品中Fe2O3的质量是________Kg。(摩尔质量/g·mol-1

FeCO3 116 Fe2O3 160 FeO 72)

答案:

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参考答案:D解析:本题考核债务承担、保证。(1)当事人对保证方式没有约定或者约定不明确的,按照连带责任保证承担保证责任。协议中对张某提供的保证方式未作约定,应当认定为连带责任保证。连带责任保证的债务...

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