试题与答案

某兴趣小组设计出下图所示装置来进行“铜与硝酸反应”实验,以探究化学实验的绿色化。

题型:实验题

题目:

某兴趣小组设计出下图所示装置来进行“铜与硝酸反应”实验,以探究化学实验的绿色化。

(1)实验前,关闭活塞b,试管d 中加水至浸没长导管口,塞紧试管c和d的胶塞,加热c,其目的是

___________________。

(2)在d中加适量NaOH溶液,c中放一小块铜片,由分液漏斗a向c中加入2mL浓硝酸。c中反应的化学方程式是__________________;再由a向c中加2mL蒸馏水,c中的实验现象是___________________。

(3)上表是制取硝酸铜的三种方案,能体现绿色化学理念的最佳方案是_________________________,原因是________________________。

(4)该小组还用上述装置进行实验证明氧化性KMnO4>Cl2>Br2,则c中加入的试剂是_________d中加入的试剂是__________,实验现象为_______________,但此实验的不足之处是_____________________。

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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