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由卤代烷制备醚,亲核试剂选择

单选题
2021-09-02 17:17
A、氧根负离子
B、氧基负离子
C、醇负离子
D、素负离子
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正确答案
B

试题解析

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由卤代烷制备醚,亲核试剂选择
卤代烷灭火系统模拟喷气试验时,宜采用()进行。
卤代烷灭火系统模拟喷气试验采用()进行。
伯卤代烷的水解反应过程中,碳氧键的形成和碳卤键的裂解系同时、连续地进行。化学反应速度与作用物和碱(亲核试剂)的浓度有关,反应是一步完成的,所以此反应是SN2反应,在化学动力学上为()
卤代烷灭火系统模拟喷气试验宜采用()进行。
卤代烷灭火剂的灭火机理是()。
Mainly east 3 or 4 partly cloudy to overcast occasional rain()slowly south moderate or good.
()any case or suspected case of quarantinable disease,or any case of eruptive disease or any death be discovered,the local quarantine officer must be notified immediately.
Should any case or suspected case of quarantinable disease,or any case of eruptive disease or any death be discovered,the local Quarantine Officer must be()immediately.
Masters are()solely responsible for all damages or accidents of whatever kind resulting from the navigating or handling of their vessels by day or by night.
If he is a common carrier,he is absolutely responsible to the owner of the goods carried ()any loss or damage to them unless caused by an Act of God or the Queen’s enemies,or the inherent vice in the goods themselves,or the negligence of the owner of the goods,or a general average sacrifice.
系统中雷达状态包括Unknown、Operational(or ON)、Failed(or OFF)、Detached。
Owners are to be responsible for loss of or damage to the goods or delay in delivery of the goods only in case the loss,damage or delay has been caused by the improper or negligent stowage of the goods.This means that().
The carrier is liable for loss of or damage to the goods or delay in delivery caused by fire,()the claimant proves that the fire arose from fault or neglect on the part of the carrier,his servants or agents.
Shutdown price(or point,or rule) 停业价格(或停业点、停业原则)
翻译:With Average or With Particular Average(WA or WPA)()
()shall be liable for loss of and damage to the Vessel and/or goods arising or resulting from inaccuracies in stating the description,quantity,weight,measurement or contents.
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