多原子分子氰(CN)2、硫氰(SCN)2和(OCN)2的性质与卤素单质(Cl2、

题型:填空题

问题:

多原子分子氰(CN)2、硫氰(SCN)2和(OCN)2的性质与卤素单质(Cl2、Br2等)相似,故称它们为拟卤素。它们可以生成酸和盐(见下表,表中X代表F、Cl、Br或I)。

 卤素硫氰
“单质”X2[(CN)2(SCN)2(OCN)2
HXHCNHOCN
KXKCNKSCNKOCN
 

(1)在表中①②空格处应分别填写_______、_______。

(2)①(CN)2和KOH溶液反应的化学方程式为:__________________________。

②已知阴离子的还原性强弱为:Cl<Br<CN<SCN<I。试写出在NaBr和KSCN的混合溶液中加入(CN)2反应的离子方程式:____________________________________。

考点:离子方程式
题型:填空题

按如图所示装置进行实验(其中C1、C2均是石墨电极),下列说法中错误的是(  )

A.甲池中,Cu极上有气泡放出

B.发现a点附近显红色

C.在C1、C2电极上所产生气体的体积比为2:1

D.乙池溶液的pH减小

题型:填空题

某女,50岁,缺失,前牙区Ⅲ°深覆,余留牙无异常。

可摘局部义齿卡环可放置在()。

A.

B.

C.

D.

E.

题型:填空题

导致急性心肌梗死患者早期(24小时内)死亡的主要原因为

A.心脏破裂

B.心律失常

C.心源性休克

D.肺栓塞

E.心力衰竭

题型:填空题

What’s your earliest childhood memory Can you remember learning to walk Or talk The first time you heard thunder or watched a television program Adults seldom (1) events much earlier than the year or so before entering school, (2) children younger than three or four (3) retain any specific, personal experiences.

A variety of explanations have been (4) by psychologists for this "childhood amnesia". One argues that the hippo-campus; the region of the brain which is (5) for forming memories, does not mature until about the age of two. But the most popular theory (6) that, since adults don’t think like children, they cannot (7) childhood memories. Adults think in words, and their life memories are like stories or (8) one event follows (9) as in a novel or film. But when they search through their mental (10) for early childhood memories to add to this verbal life story, they don’t find any that fit the (11) . It’s like trying to find a Chinese word in an English dictionary.

Now psychologist Annette Simms of the New York State University offers a new (12) for childhood amnesia. She argues that there simply aren’t any early childhood memories to (13) . According to Dr. Simms, children need to learn to use someone else’s spoken description of their personal (14) in order to turn their own short-term, quickly forgotten (15) of them into long-term memories. In other (16) , children have to talk about their experiences and hear others talk about (17) --Mother talking about the afternoon (18) looking for seashells at the beach or Dad asking them about their day at Oceanz Park. Without this (19) reinforcement, says Dr. Simms, children cannot form (20) memories of their personal experiences.

Notes: childhood amnesia 儿童失忆症。

(17)()

A.him

B.their

C.it

D.them

题型:填空题

《建设工程委托监理合同(示范文本)》规定,监理人在责任期内如因过失而造成经济损失,要负( )的责任。

A.违约

B.缔约过失

C.监理失职

D.全部损失

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