在醛与银氨溶液的反应中,银氨溶液必须现用现制,要求氨水和硝酸银溶液的浓度要小(通

题型:选择题

问题:

在醛与银氨溶液的反应中,银氨溶液必须现用现制,要求氨水和硝酸银溶液的浓度要小(通常为2%),并且加 氨水的量保证恰好使沉淀溶解,氨水最好不过量。 AgNO3+NH3·H2O==AgOH↓+NH4NO3

AgOH+2NH3·H2O==Ag(NH3)2OH+2H2O 请问:氢氧化银溶于氨水所得的银氨溶液的pH [ ]

A.比原氨水的pH大

B.比原氨水的pH小

C.与原氨水的pH一样

D.无法估计

考点:溶液的酸碱性
题型:选择题

阅读填空。

     (1) E_______ country has its favorite food, Italians like pizzas, Indians like hot food, and Japanese like to

 (2) e_______ fish. Often they don't cook it.

     In England, one of the most popular kind of food is fish and chips. People (3) u_______ buy it in a fish and

chip (4) s_______. They put it in paper (5) b_______, and (6) t_______ it home or to their workplaces.

Sometimes, they eat it on the road.

     It seems that American fast food is the most popular in the world. In New York, Paris, London, and even

some big (7) c_______ in China, you can find people eat hamburgers and chips.

     Chinese food is (8) a_______ very popular in the world. You can find Chinese restaurants in many cities.

People (9) e_______ Chinese food (10) b_______ it has different tastes and is usually very delicious!

题型:选择题

下列属于侵犯他人隐私权的是[     ]

A.父母拆看未满10周岁子女的信件 

B.因好奇窃取他人的QQ号密码偷看他人的聊天记录 

C.某出版社出版了某电视节目主持人写的自传 

D.某电视台法制栏目播出对某贪官的庭审实录 

题型:选择题

淋证临床上有六淋之分,若湿热客于下焦,膀胱气化不利,小便灼热刺痛,则为()

A.气淋

B.膏淋

C.热淋

D.血淋

E.石淋

题型:选择题

关于使用维护助手安装CTI平台,在“安装前准备”的步骤中,以下描述错误的有()。

A.如果选择的是双机同时部署,则输入用户信息时,只需要在其中一个节点输入即可

B.提供了用户名、密码、用户家目录、用户所属组等信息的输入

C.如果用户未创建,维护助手会自动创建用户

D.如果用户已经存在,会删除该用户重建

题型:选择题

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