关于一氧化碳还原氧化铜的实验,三个组的同学设计了如下甲、乙、丙三套实验装置,请根

题型:实验题

问题:

关于一氧化碳还原氧化铜的实验,三个组的同学设计了如下甲、乙、丙三套实验装置,请根据下列要求回答有关问题:

①实验开始时,要先 ____ 然后 ____ ,其目的是排尽空气,防止爆炸;实验结束时,为了防止 _____ ,要注意先停止加热,继续通一氧化碳直到冷却.

②实验过程中,A管内发生化学反应的现象是 ________ ,化学方程式是 _____________ ,B管内的发生反应的现象是 ____________ 反应的化学方程式是 ________________

③装置丙与装置乙相比,它的主要优点是 ________________

④如果对甲装置进行改进,可用于实验室证明碳与氧化铜的反应,此反应的化学方程式为 ___________________ ,发生还原反应的物质是 ___________ ,需要对甲装置做哪些改进 _______________

考点:一氧化碳还原氧化铜
题型:实验题

R&D人员折合全时当量中的科学家和工程师的全时当量包括()

A.参加R&D项目人员中的科学家的全时当量

B.参加R&D项目人员中的工程师的全时当量

C.应分摊在R&D项目上的管理人员中科学家和工程师的全时当量

D.应分摊在R&D项目上的直接服务人员中科学家和工程师的全时当量

E.参加R&D项目人员的折合当量

题型:实验题
My father was raised in a fatherless home at a time when the family of five struggled to survive, which caused my father to be extremely tightfisted(吝啬) with money.
When we children became    16  that other children got pocket money from their parents, we made a(n)   17  to ask our father from some. Immediately his face turned stone-cold, and he said, “If you’re old enough to ask, you’re old enough to    18 .” And we had to seek odd jobs about the neighborhood.
He didn’t    19  his attitude as we grew into adulthood. There was a time when    20  of us had a car, so we had to ride a    21  whenever we came home. Though the bus stopped about two miles from home, Dad never met us, 22  in bad weather. If someone    23  (and my brothers did a lot), he’d say in his    24  father-voice. “That’s what your legs are    25  !
One spring morning I was on the bus home from    26 . Tests and long hours in labs had    27  me exhausted. As other students were    28  at their stops. I looked silently out of the window. Finally, the bus came to a    29  at my destination, and I    30 , carrying my suitcase to begin the long journey home.
The row of privet hedge(树篱) came into    31 , which lined the driveway that climbed the hill to our house. I stopped to put a book in the suitcase. When I stood up, I saw something gray    32  along the top of the hedge toward the house.
It was the top of my father’s head. I    33  then, each time I came home, he would stand behind the hedge, watching,    34  he knew I had arrived safely. I held back my tears. He did care,   35 .
Upon reaching home, I found my father innocently in his chair. “So! It’s you!” he said, his face lengthening into surprise.
小题1:
A.aware B.certain C.surprised D.excited
小题2:
A.attempt B.suggestionC.troubleD.plan
小题3:
A.spendB.earnC.surviveD.raise
小题4:
A.strengthenB.softenC.takeD.show
小题5:
A.neither B.eachC.allD.none
小题6:
A.bicycleB.car C.train D.bus
小题7:
A.especiallyB.onlyC.evenD.once
小题8:
A.refusedB.complainedC.criedD.intended
小题9:
A.strangestB.lowestC.softestD.scariest
小题10:
A.onB.inC.byD.for
小题11:
A.workB.homeC.townD.college
小题12:
A.ledB.madeC.foundD.proved
小题13:
A.treatedB.receivedC.metD.greeted
小题14:
A.stopB.houseC.streetD.corner
小题15:
A.stepped offB.went offC.jumped onD.climbed on
小题16:
A.mindB.viewC.flowerD.leaf
小题17:
A.shiningB.flyingC.failingD.moving
小题18:
A.understoodB.thoughtC.imaginedD.realized
小题19:
A.sinceB.afterC.until D.though
小题20:
A.after allB.above allC.in advanceD.in total
题型:实验题

A公司对外负债130万元,另有30万元的货款未予追回(欠款人为D公司)。20印年3月A公司经全体股东同意分立为B、C两个公司,由B承受A公司的全部债权债务,并办理变更登记与公告。同年4月,B、C签订协议,约定A公司对D公司的30万元债权由C享有。同年5月, C向法院起诉D,要求归还30万元货款。有关该案的正确表述是下列哪项( )

A.B、C之间的协议有效,D应向C偿还30万元货款
B.B、C之间的协议有效,但未经通知,C无权向D追索货款
C. B、c之间的协议有效,但不得对抗善意第三人,故C无权向D追索贷款
D.B、C之间的协议有效,但D有权选择向 B或C履行义务

题型:实验题

如图所示装置中,挡板将容器分成相等的两部分,左边容器装满水,右边容器装满水银,一匀质球可绕固定的水平轴O 转动,则下列说法正确的是   

[ ]

A.右边半球所受的浮力大于左边半球所受的浮力    

B.在浮力力矩的作用下球将绕轴转动    

C.球不能转动,因为它属于第一类永动机    

D.球体所受的浮力对轴O的转动力矩为零

题型:实验题

封髓丹功效与作用

更多题库