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问题 选择题

下列操作不能达到实验目的的是

 目的操作
A在溶液中将MnO4－完全转化为Mn2+向酸性KMnO4溶液中滴加溶液至紫色消失
B除去KNO3中少量NaCl将混合物制成热的饱和溶液，冷却结晶，过滤
C配制980mL0.1mol/LCuSO4溶液将25.0gCuSO4·5H2O溶于水配制成1L溶液
D确定蔗糖是否水解取水解液滴加少量新制的Cu(OH)2悬浊液，加热
 

答案

答案：D

题目分析：蔗糖是非还原性糖，在酸作用下水解生成葡萄糖和果糖具有还原性，需要先加入氢氧化钠中和硫酸呈碱性，再加入银氨溶液加热出现银镜现象，证明蔗糖水解，故选D；

单项选择题

出境货物报检单所列各栏必须填写完整、准确、清晰，栏目内容确实无法填写的以( )表示。

A．***

B．留空

C．√

D．×
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填空题

Part 2


Questions 9-18


·Read the following passage and answer questions 9-18.
1. When one of your car tires goes flat, there are two things you can do. Groan and change or, if you don’t have a spare, stand helplessly behind the road and hope someone to your rescue. Now comes a third alternative, called Quickwheel. It is designed to get disabled motorists rolling again as quickly as possible.
2. Quickwheel is essentially a tiny trailer — complete with three tough little wheels of it’s own — that support the flat tire and enable the motorist to drive to the service station without losing much time or expending much energy. The product is manufactured in the Netherlands but is owned and marketed by a US company. Quickwheel inc. of Greenwich, Connecticut. According to the firm’s president, Robert Bockweg, the product meets each of the major concerns that consumers associate with flat tires: safety lost time and physical exertion.
3. To use it, motorists simply unfold the product to its fully extended position, set it in front of the disabled tire, drive the car on to the Quickwheel’s ramp and attach a special safety strap over the tire. The tire is then locked, or cradled, in Quickwheel’s metal frame. The device’s three wheels do the rest of work.
4. According to Quckwheel Inc., its product can be driven "four miles" at speeds of up to 45 miles per hour without any noticeable change in the vehicle’s breaking or steer operation. The company also claims that it can be used on just any type of car, jeep, mini-van or trailer.
5. Bockweg says that Quickwheel will be sold in the US, at a price of $150. Distribution agreements now being negotiated should make the product available in Japan, Canada and West Europe in the future.

Questions 9-13


·For questions 9-13, choose the best title for each paragraph from below.
·For each numberedparagraph (1-5), mark one letter (A-G) on the Answer Sheet.
·Do not mark any letter twice.
  • A. The future marketing of Quickwheel.
  • B. The advantages of the Quickwheel.
  • C. How does Quickwheel work
  • D. The ways of dealing with flat tires.
  • E. Quickwheel can get disabled motorists rolling again.
  • F. An introduction of Quickwheel.
  • G. Why is the Quickwheel invented

Paragraph 2: ______
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