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实验室用铜制取硫酸铜,将适量硝酸分多次加入到铜粉与稀硫酸的混合物中,加热使之反应完全,通过蒸发、结晶得到硫酸铜晶体。
(1)为了节约原料,硫酸和硝酸的物质的量之比最佳为:    ;为了吸收该反应中产生的尾气,请选择下列中合适的装置       

(2)为符合绿色化学的要求,某研究性学习小组进行如下设计:
第一组:以空气为氧化剂法
方案1:以空气为氧化剂。将铜粉在仪器B中反复灼烧,使铜与空气充分反应生成氧化铜,再将氧化铜与稀硫酸反应。
方案2:将空气或氧气直接通入到铜粉与稀硫酸的混合物中,发现在常温下几乎不反应。向反应液中加少量FeSO4,即发生反应,生成硫酸铜。反应完全后,加物质甲调节pH ,铁元素全部沉淀(一般认为铁离子的浓度下降到10-5mol·L-1,就认为沉淀完全),然后过滤、浓缩、结晶。
已知:Ksp[Cu((OH)2]≈10-22, Ksp[Fe((OH)2]≈10-16,  Ksp[Fe((OH)3]≈10-38
请回答下列问题:
如开始加入的铜粉为3.2 g,最后所得溶液为500 mL,溶液中含有铁元素0.005 mol。
①方案1中的B仪器名称是       
②为了使铁元素全部沉淀,应调节pH至少为_________。
③方案2中甲物质可选用的是             
A.CaOB.NaOHC.CuCO3D.Cu2(OH)2CO3 E、Fe2(SO4)3
④反应中加入少量FeSO4可加速铜的氧化,用离子方程式解释其原因        
第二组:过氧化氢为氧化剂法
将3.2g铜丝放到45 mL 1.5mol·L-1的稀硫酸中,控温在50℃。加入18mL 10%的H2O2,反应0.5h,升温到60℃,持续反应1 h后,过滤、蒸发浓缩、减压抽滤等,用少量95%的酒精淋洗后晾干,得CuSO4·5H2O 10.5g。
请回答下列问题:
⑤反应时温度控制在50℃~60℃不宜过高的原因是         
⑥本实验CuSO4·5H2O的产率为         

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根据对话内容,选择恰当的句子补全下列对话。
(H for Henry; J for Janet)
H: Hi, Janet, Would you like to help save the environment?
J:  I don't know. 1______
H: Well, first, you can start by turning off the lights.
J:  Yes. That's easy. Sometimes I turn on the lights without thinking. 2______
H: Second, you can ride a bicycle. 3______
J:  That will save money, too. What else?
H: Third, try to recycle paper.
J:  Mm. We get a lot of paper at home. Good idea.
H:  The fourth idea is turning off the shower when you're not using it.
J:  You mean, when I have shampoo (洗发剂) in my hair?
H: Yes. 4______. Every minute helps. And fifth, take a bag when you go shopping.
     Don't use plastic bags (塑料袋).
J:  OK. 5______. I'll tell them.
A. I disagree with you.
B. We have to save water.
C. My parents do most of the shopping.
D. Don't take a bus or a taxi if you don't have to.
E. What's next?
F. I never do that.
G. What can I do?

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根据对话内容,选择恰当的句子补全下列对话。

(H for Henry; J for Janet)

H:Hi, Janet, Would you like to help save the environment?

J:I don't know.  1  

H:Well, first, you can start by turning off the lights.

J:Yes.That's easy.Sometimes I turn on the lights without thinking.  2  

H:Second, you can ride a bicycle.  3  

J:That will save money, too.What else?

H:Third, try to recycle paper.

J:Mm.We get a lot of paper at home.Good idea.

H:The fourth idea is turning off the shower when you're not using it.

J:You mean, when I have shampoo(洗发剂)in my hair?

H:Yes.  4   Every minute helps.And fifth, take a bag when you go shopping.Don't use plastic bags(塑料袋).

J:OK.  5  .I'll tell them.

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