问题 填空题

2013年合肥市化学实验考试试题之一就是探究金属的某些物理性质和化学性质,该实验内容之一是:用镊子将打磨后的铝片放入试管中,然后倒入约3mL的稀盐酸.同学们在实验过程中发现,铝片一开始和稀盐酸反应只是冒出小气泡,过一段时间后才变得越来越快.请你和同学们一道探究铝与稀盐酸的反应速率究竟受到什么因素的影响?

(1)写出铝与盐酸反应的化学方程式______;

(2)【猜想一】温度越高,反应速率越快?

【猜想依据】活泼金属和盐酸反应是______(填写“放热”或“吸热”)反应;

【进行实验】在实验开始和实验很剧烈的时候分别轻触试管外壁,会发现试管温度______;

【实验拓展】同学们也发现,时间在延长一点,铝片和酸反应的速率又会降低下来,你认为可能的原因是______;

【设计实验】

实验方案预期现象
(6)(注意:若答对本小题奖励4分,化学试卷总分不超过60分.)

你认为影响铝和盐酸反应速率的因素还有______.

实验方案预期现象及结论
实验一
实验二

答案

(1)铝和稀盐酸反应生成氯化铝和氢气,故答案:2Al+6HCl=2AlCl3+3H2↑.

(2)镁和稀盐酸反应放热和影响反应速率的因素:酸的浓度、金属的纯度,盐酸的浓度越高反应速率越快;金属越纯与酸反应的速度越快.故答案:放热   升高   盐酸的浓度降低.

(6)影响反应速率的因素:酸的浓度、金属的纯度,金属的纯度越高反应速率越快,故答案:铝的纯度

完形填空

Passing Your Love On
Waiting for the airplane to take off, I was happy to get a seat by myself. Just then, an air hostess approached me and asked, “Would you mind  36  your seat? A couple would like to sit together.” The only  37  seat was next to a girl with her arms in casts(石膏绷带), a black-and-blue face, and a sad  38 . “No way am I going to sit there,” I thought immediately. But a soft voice spoke, “She needs help.” Finally, I  39  to move to that seat.
The girl was named Kathy. She had been in a car accident and  40  was on her way for  41 .
When the snack and juice arrived, it did not take me long to  42  that Kathy would not be able to  43  herself. I considered  44  to feed her but hesitated, as it seemed too  45  to offer a service to a  46 . But then I realized that Kathy’s need was more  47  than my discomfort. I offered to help her eat, and  48  she was uncomfortable to accept, she  49  as I expected. We became closer and closer in a short period of time. By the end of the five-hour trip, my heart had  50 , and the time was really  51  spent than if I had just sat by myself.
I was very glad I had reached  52  my comfort zone to sit next to Kathy and feed her. Love  53  flows beyond human borders and removes the fears that keep us  54 . When we stretch to serve another, we grow to live  55  a larger and more rewarding world.
小题1:
A.leaving B.changingC.takingD.giving
小题2:
A.comfortableB.suitable C.available D.favorable
小题3:
A.heartB.expression C.action D.thought
小题4:
A.decided B.wanted C.regrettedD.promised
小题5:
A.immediatelyB.lately C.recently D.now
小题6:
A.treatment B.travel C.pleasure D.business
小题7:
A.know B.say C.realize D.recognize
小题8:
A.eat B.feed C.choose D.support
小题9:
A.offering B.needing C.stopping D.trying
小题10:
A.impolite B.far C.close D.fast
小题11:
A.girl B.neighbor C.passenger D.stranger
小题12:
A.unusual B.directC.importantD.shameful
小题13:
A.when B.although C.since D.as
小题14:
A.refused B.wondered C.cried D.did
小题15:
A.warmed B.jumped C.broken D.cheered
小题16:
A.good B.worse C.better D.bad
小题17:
A.below B.through C.across D.beyond
小题18:
A.seldom B.never C.hardly D.sometimes
小题19:
A.separate B.independentC.silent D.upset
小题20:
A.of B.in C.at D.for
多项选择题