问题 选择题

某同学按下图所示的装置进行电解实验。下列说法正确(  )

 

A.电解过程中,铜电极上有H2产生

B.电解过程中,铜电极不断溶解

C.电解过程中,石墨电极上始终有铜析出

D.整个电解过程中,H的浓度不断增大

答案

答案:B

Cu和电源的正极相连,所以Cu做阳极,并失电子变成铜离子,阳极反应:Cu-2e=Cu2+;石墨和电源的负极相连,做阴极,溶液中的氢离子得电子变成氢气,阴极反应:H++2e=H2↑,所以正确的答案选B。

填空题

In its more extreme forms persecution mania is a recognized

form of insanity. Some people imagine that others wish to kill

them, or imprison them, or to do them some other grave injury.

Often the wish to protect themselves from imaginary persecutors   (1)______

leads them into acts of violence which make it necessary to restrain

their liberty. This, like many other forms of insanity, is

only an exaggeration of tendency not at all uncommon among      (2)______

people who count as normal. I do not propose to discuss

the extreme forms, that are a matter for a psychiatrist.       (3)______

It is the milder forms that I wish to consider, since they      (4)______

are a very frequent cause of unhappiness, and because, not having

gone much far as to produce definite insanity, they          (5)______

are still capable of being dealt by the patient himself,       (6)______

provided he can be induced to diagnose his trouble

right and to see that its origin lies within himself and        (7)______

not in the supposed hostility and unkindness of others.        (8)______

We are all familiar with the type of person, man or woman,

who, according to his own account, is perpetually the victim

of ingratitude, unkindness, and treachery. People of such kind     (9)______

are often extraordinarily plausible, and secure warm sympathy

from those who have not known them long. There

is, as a rule, nothing inherently improbable about every separate    (10)______

story that they relate.

8()

单项选择题