某烃A蒸气密度是相同状况下氢气密度的53倍,10.6 g A在O2中燃烧生成CO

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问题:

某烃A蒸气密度是相同状况下氢气密度的53倍,10.6 g A在O2中燃烧生成CO、CO2和9 g H2O.烃A不能使Br2的CCl4溶液褪色,但能使KMnO4酸性溶液褪色,其一氯代物有2种.   已知:

A可以发生下面一系列的变化.

根据上述转化关系回答下列问题:

(1)试写出下列物质的结构简式:A   ,C    ,F    .

(2)指出上述①②的反应类型:①         ,②         .

(3)写出E+G→H的化学方程式                                    .

考点:有机物的推断
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将下面A——F 五个句子分别填入文中空缺处,使短文意思通顺完整。(5分)

Have you ever done something silly that made you feel so embarrassed(尴尬的)? Well, I had a really bad Saturday morning last week.

I went to town to do some shopping. While I was walking home, it began to rain.     小题1:  , because I didn’t have an umbrella. It was raining hard and I decided to stay in the phone box until it stopped.

A few minutes later, I saw a young man walk up to the phone box, wearing a yellow raincoat and holdinga tool box.    小题2:   , so I pick up the phone and act to talk to someone. I thought the man would go away, but he didn’t. He just waited in the heavy rain, watching me wave my hands about and act as if I was deep in conversation.

Luckily, the rain stopped after about ten minutes. “OK. Mum,” I said loudly into the phone, “I’ll see you later. Bye!”    小题3:   .

“I’m sorry to keep you waitingfor so long.” I said to the man.

“Oh,     小题4:  ,” he answered. “I’ve just come to mend it. It doesn’t work, you see.”

    小题5:  , and I quickly ran off with my head down. That was certainly the most embarrassed of my life.

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肌肉受到刺激会产生收缩,肌肉受刺激前后肌细胞膜内外的电位变化和神经纤维的电位变化一样。现取两个新鲜的神经一肌肉标本,将左侧标本的神经搭在右侧标本的肌肉上,此时神经纤维与肌肉细胞相连接(实验期间用生理盐水湿润标本),如图所示。图中②、④指的是神经纤维与肌细胞之间的接头,此接头与突触结构类似。刺激①可引起右肌肉收缩,左肌肉也随之收缩。请回答:

(1)①、②、③、④中能进行兴奋传递的是______(填写标号);能进行兴奋传导的是________(填写标号)。

(2)右肌肉兴奋时,其细胞膜内外形成的________电流会对③的神经纤维产生_______作用,从而引起③的神经纤维兴奋。

(3)直接刺激③会引起收缩的肌肉是_________________。

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下列实验方案正确的是

选项   实验目的   所用试剂或方法
A除去硫酸镁溶液中的硫酸加入过量的Ba(OH)2溶液,过滤
B分离氯化钠和硝酸钠固体混合物I加水溶解后,过滤,蒸发结晶
C鉴别氯化铵和氯化钙分别加入熟石灰,研磨,闻气味
D鉴别羊毛织物和涤纶织物,                                
 

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证券服务部可以由证券公司和其他机构联营或委托经营。

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工作温度较高,磨损较严重和加工较粗糙的磨擦表面。应选用()的润滑油。

A.粘度较大

B.粘度较小

C.凝固点大

D.凝固点低

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