如图为某有机物的结构简式,每个节点处代表有一个碳原子,与其结合的氢原子的元素符号

题型:选择题

问题:

如图为某有机物的结构简式,每个节点处代表有一个碳原子,与其结合的氢原子的元素符号省略,这种化学式称为“键线式”。又知酯类在铜铬氧化物(CuO·CuCrO4)催化下,与氢气反应得到醇,羰基双键可同时被还原,但苯环在催化氢化过程中不变,其反应原理如下:

关于该化合物的下列说法中,正确的是

A.该有机物的化学式为C20H14O5

B.1mol该有机物与浓溴水反应,消耗5molBr2

C.与足量氢氧化钠溶液充分反应,所得产物中相对分子质量较小的钠盐为HCOONa

D.1mol该有机物在铜铬氧化物催化下能与2mol氢气发生反应

考点:芳香烃的通式卤代烃苯的同系物
题型:选择题

排泄性胆道系统造影服用脂肪餐的意义,与下列选项无关的是()

A.胆囊收缩后可进一步明确诊断

B.胆囊功能性疾病的诊断

C.胆总管的显示

D.鉴别阳性结石

E.胆囊与肠内容或肠气的分离

题型:选择题

、如右图所示电源电动势为ε、内电阻为r。调整电路的可变电阻R的阻值,使电压表V的示数增大ΔU,在这个过程中 (    )

A.通过R1的电流增加,增加量一定等于ΔU/R1

B.R2两端的电压减小,减少量一定等于ΔU

C.通过R2的电流减小,减少量一定等于ΔU/R2

D.路端电压增加,增加量一定等于ΔU

题型:选择题

阅读下面短文,掌握其大意,从每题所给的A、B、C、D四个选项中,选出最佳选项,并在答题卡上讲该项涂黑。

A Race Against Death

It was a cold January in 1925 in North Alaska. The town was cut off from the rest of the world due to heavy snow.

On the 20th of that month, Dr.Welch   36   a Sick boy, Billy, and knew he had diphtheria, a deadly infectious(传染的)disease mainly affecting children. The children of Nome would be  37  if it struck the town. Dr.Welch needed medicine as soon as possible to stop other kids from getting sick.   38  , the closest supply was over 1,000 miles away, in Anchorage.

How could the medicine get to Nome? The town`s  39  was already full of ice, so it couldn`t come by ship. Cars and horses couldn`t travel on the   40  roads. Jet airplanes and big trucks didn`t exist yet.

41  January 26, Billy and three other children had died. Twemty more were   42  . Nome`s town officials came up with a(n)  43  . They would have the medicine sent by   44  from Anchorage to Nenana. From there, dogeled(狗拉雪橇)drivers—known as “mushers”—would   45  it to Nome in a relay(接力).

The race began on January 27. The first musher, Shannon, picked up the medicine from the train at Nenana and rode all night.  46  he handed the medicine to the next musher, Shannon`s face was black from the extreme cold.

On January 31, a musher named Seppala had to   47  a frozen body of water called Norton Sound .It was the most  48  part of the journey. Norton Sound was covered with ice,which could sometimes break up without warning.If that happened,Seppala might fall into the icy water below.He would  49  ,and so would the sick children of  Nome.But  Seppala made it across.

A huge snowstorm hit on February 1.Amusher  named Kaasen had to brave this storm.At one point,huge piles of sonw blocked his 50  .He had to leave the trail (雪橇痕迹)to get around them.Conditions were so bad that it was impossible for him to  51  the trail again. The only hope was Balto,Kaasen’s lead dog, Balto put his nose to the ground, 5 2  to find the smell of other dogs that had traveled on the trail.If  Balto failed,it would mean disaster for Nome.The minutes passed by.Suddenly, Balto began to  53  .He had foung the trail

At 5:30 am on February 2, Kaasen and his dog  54  in Nome. Within minutes,Dr.Welch had the medicine.He quickly gave it to the sick children.All of them recoverd.

Nome had been  55  .

55()

A.controlled

B.saved

C.founded

D.developed

题型:选择题

有关硫喷妥钠麻醉,下列哪项不正确()

A.交感神经受抑制较明显,副交感神经的作用占优势

B.对呼吸中枢抑制明显

C.禁用于可疑紫质症病人

D.男、女诱导用量相同

E.快速耐药性

题型:选择题

二进制数1100100转换成十进制整数等于

A.96

B.100

C.104

D.1 12

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