试题与答案

酸性气进炉前为什么要脱水?

题型:问答题 简答题

题目:

酸性气进炉前为什么要脱水?

答案:

参考答案:

1、水带进炉后,会降低炉温,甚至熄火,影响炉子寿命; 

2、水进炉后产生大量蒸汽,增加系统压力,严重时,造成炉子爆炸; 

3、水蒸汽增多,影响硫化氢的转化率; 

4、增加设备和管线的腐蚀; 

5、影响催化剂的活性和寿命。

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(4分)某班同学想探究红砖粉末是否也可作为过氧化氢分解的催化剂,请你一起参与他们的探究过程,并填写下列空白:

(1)【提出问题】红砖粉末能不能做过氧化氢分解呢?

(2)【猜想】红砖粉末能做过氧化氢分解的催化剂

(3)【实验验证】

 实验步骤实验现象实验结论
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实验二在装有过氧化氢溶液试管中加入红砖粉末,然后将带火星木条伸入试管中木条复燃__________________
(4)【讨论与反思】有同学认为:仅凭上述两个实验还不能证明红砖粉末能做过氧化氢的催化剂,还需要增加一个实验:实验三:________________________________________。

(5)【实验步骤】①准确称量红砖粉末质量;②完成实验二;③待反应结束,将实验二试管中物质进行过滤、洗涤、干燥、称量红砖粉末的质量;④对比反应前后红砖粉末质量。

(6)【分析】如果红砖粉末反应前后质量不变,则说明红砖粉末可以作为过氧化氢的催化剂。但也有同学认为:要证明猜想,上述三个实验还是不够,还需要再补充一个实验:你认为还需要探究:实验三中得到的红砖粉末能否______________________________。

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