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问题 填空题

铝、铁、铜是应用最普遍的金属。

（1）铜是印刷电路工业的重要材料。用H2O2和H2SO4的混合溶液可溶出印刷电路板金属粉末中的铜,是工业上采用的方法之一。已知

Cu(s) + 2H+(aq) ="=" Cu2+(aq) + H2(g)  △H= +64.39kJ/mol

2H2O2(l) ="=" 2H2O(l) + O2 (g)  △H= ﹣196.46kJ/mol

H2(g) +1/2 O2 (g)="=" H2O(l)  △H= ﹣285.84kJ/mol

在H2SO4溶液中Cu和H2O2反应生成Cu2+和H2O的热化学方程式为

                                              

（2）镁铝合金生活中应用广泛。取样品a克，溶于200ml 5mol/L的HCl溶液，收集到标况下氢气3.36L，a的取值范围               ，向反应后溶液中加入4mol/L NaOH溶液       ml,沉淀质量达到最大值。

（3）标准状况下，铁铜合金ag加入足量稀硝酸中，收集了一定量气体NO，在混合了67.2mlO2后，可完全被H2O吸收，无气体剩余。则生成的NO为    ml；向反应后溶液加足量的NaOH溶液，得到沉淀的质量          g。（用含a的代数式表示）

答案

（1）  Cu(s) +2H+ (aq) + H2O2(l) ="=" Cu2+(aq) + 2H2O(l)  ⊿H= -319.68 kJ/mol

（2）  （2.7   3.6）                   250   

（3）   89.6               a+0.204     

单项选择题

下列程序段的输出结果是 ( ) String MyStr="Hello，"； MyStr=MyStr+"World!"； System.out.println(MyStr);

A．Hello，World!

B．Hell

C．World!

D．该程序段有语法错误
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问答题

On 1 July 2006, for the purpose of buying a shipment of a wooden plate, Oriental Construction Materials Company (Oriental Company) sent a purchase order to Wooden Company which contained the terms and conditions of the wooden plate, including quantity, quality, way of payment and time of shipment. The purchase order also indicated that Wooden Company should reply within 10 days upon receipt of the purchase order.On 9 July 2006 Wooden Company sent back a fax and accepted all the terms and conditions of the purchase order, and added the price of the said wooden plate. The fax indicated that Oriental Company should give its final decision within three days upon receipt of the fax.On 11 July 2006 Oriental Company replied with a fax accepting the price forwarded by Wooden Company and demanded that a written letter of confirmation was required for finally concluding a contract.On 15 July 2006 Wooden Company despatched a written confirmation letter, via a DHL package, which contained all the terms and conditions for the sales of the wooden plate as agreed upon by the two parties. The written confirmation letter also provided that the liquidated damages amounting to 10% of the total price of the goods would be borne by the breaching party as the liability for breach of contract.Just during the period of the negotiations between the two parties, the market price of the wooden plate rose quickly. Oriental Company urged Wooden Company to deliver the goods according to the terms of the written confirmation letter, which it alleged to constitute an effective contract, without any delay. However, Wooden Company insisted there was no contract at all between the parties. Under such circumstances Oriental Company filed a law suit against Wooden Company in the local court.Required:Answer the following questions in accordance with the relevant provisions of the Contract Law of China and give your reasons for your answer:

(b) Explain whether there was a contract between the two parties. (4 marks)
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