X、Y、Z、M是元素周期表中前20号元素,其原子序数依次增大,且X、Y、Z相邻.

题型:选择题

问题:

X、Y、Z、M是元素周期表中前20号元素,其原子序数依次增大,且X、Y、Z相邻.X 的核电荷数是Y的核外电子数的一半,Y与M可形成化合物M2Y。下列说法正确的是[ ]

A.还原性:X的氢化物>Y的氢化物>Z的氢化物

B.简单离子的半径:M的离子>Z的离子>Y的离子>X的离子

C.YX2、M2Y都是含有极性键的极性分子

D.Z元素的最高价氧化物的水化物的化学式为HZO4

考点:元素周期表
题型:选择题

L≥100米的船舶,应配备:()

A.一面号锣,一个号钟

B.一个号钟,一个号笛

C.一面号锣,一个号笛

D.一面号锣,一个号钟,以及至少一个号笛

题型:选择题
It was one of those cold winter nights in the Haight-Ashbury district of San Francisco . I was driving an eyesore(丑陋的东西)that could only be  36  as a “ car ” by someone who was either a shameless liar or a good friend .
It was  37  to drive the car because you had to keep your fingers and toes crossed to keep the engine running . I tried to imagine I was driving a huge clumsy  38  ; that way I didn’t  39  the slow speed .
That night I must have uncrossed my fingers to scratch something . The car  40  in the middle of a four-lane stretch of Oak Street . I  41  for a place to turn off(拐弯), but the street was lined with parked cars .
There I sat , in  42  traffic , as tons of vehicles screamed by . In my rearview mirror(后视镜)I saw a car  43  behind me . I knew what was coming . Soon the horn would start and someone would be  44  at me . But I was  45  .
A stranger got out of the car and came to my  46  . He asked , “ Do you want a  47  ?”
I was surprised but  48  . And then he  49  to his car and two teens piled out to help push my car . When I was  50  delivered to a side street , they got back into their car and rejoined the sea of  51  . I didn’t get to  52  them .
Over the years I’ve realized something about the  53  who stopped to help . I’ve noticed that every time I’m in  54  , he appears . The one true thing in this world is an unasked  55  provided by a stranger .
小题1:
A.heard ofB.referred toC.looked downD.talked about
小题2:
A.difficultB.interestingC.funnyD.special
小题3:
A.truckB.carC.bicycleD.snail
小题4:
A.realizeB.feel C.mindD.notice
小题5:
A.gotB.diedC.slowedD.began
小题6:
A.hopedB.askedC.caredD.waited
小题7:
A.lateB.fastC.busyD.local
小题8:
A.break downB.speed upC.pass byD.pull up
小题9:
A.shoutingB.walkingC.aimingD.rushing
小题10:
A.luckyB.wrongC.stupidD.sorry
小题11:
A.mindB.wayC.windowD.seat
小题12:
A.changeB.rideC.liftD.push
小题13:
A.listenedB.insistedC.noddedD.watched
小题14:
A.wavedB.smiledC.pointedD.drove
小题15:
A.readilyB.quietlyC.simplyD.safely
小题16:
A.teensB.trafficC.passers-byD.travelers
小题17:
A.waitB.recognizeC.thankD.notice
小题18:
A.strangerB.driverC.repairmanD.friend
小题19:
A.debtB.troubleC.surpriseD.despair
小题20:
A.courageB.comfortC.suggestionD.kindness
题型:选择题

教师要充分开发习题的教育资源,使习题的()三者并重。

A.实用功能

B.知识功能

C.评价功能

D.教育功能

题型:选择题

()制订的规章制度可按程序临时申请调整计划。

A.特殊和紧急需要

B.特殊情形和紧急需要

C.特殊需要和紧急情形

D.特别紧急情形

题型:选择题

在各类有机非电解质之间,其毒性大小依次为()。

A.芳烃>醇>酮>环烃>脂肪烃

B.醇>芳烃>酮>环烃>脂肪烃

C.芳烃>酮>醇>环烃>脂肪烃

D.芳烃>醇>环烃>酮>脂肪烃

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