问题 填空题

I.根据下列化学方程式回答问题:

SiO2+2C+2Cl2

.
SiCl4+2CO

(1)反应中电子转移的数目是______.

(2)在该反应中,还原剂是______.

II.请写出下列反应的化学方程式.

(1)在制作印刷电路板的过程中常利用铜与氯化铁溶液反应______.

(2)利用铝与二氧化锰反应来制取高熔点金属锰______.

(3)过氧化钠可用作呼吸面具中的供氧剂______.

答案

I.SiO2+2C+2Cl2

.
SiCl4+2CO中,C元素的化合价升高,Cl元素的化合价降低,

(1)C元素的化合价由0升高为+2价,该反应中转移电子为2×(2-0)=4e-,故答案为:4e-

(2)因C元素的化合价升高,则C为还原剂,故答案为:C;

II.(1)铜与氯化铁溶液反应生成氯化亚铁和氯化铜,该反应为2FeCl3+Cu=2FeCl2+CuCl2

故答案为:2FeCl3+Cu=2FeCl2+CuCl2

(2)铝与二氧化锰反应生成氧化铝和Mn,该反应为4Al+3MnO2

高温
.
2Al2O3+3Mn,

故答案为:4Al+3MnO2

高温
.
2Al2O3+3Mn;

(3)过氧化钠与二氧化碳反应生成碳酸钠和氧气,该反应为2Na2O2+2CO2=2Na2CO3+O2↑,

故答案为:2Na2O2+2CO2=2Na2CO3+O2↑.

阅读理解

Whenever my dog, Barney, comes into the house after having been for a ride in the car, he runs to the pen(围栏) we have set up for him by the back door. It’s not something we intentionally trained him to do. The habit came simply because my husband tended to put him in his pen whenever they came in. After doing it a few times, Barney just figures that’s what you do when you come inside after a car ride.

It’s the same with your thinking. You get into the habit of thinking a certain way and then you’ll rarely question it after that.

This is especially true when you were growing up. You developed habits that just made things easier for you. You probably didn’t even think about them. That’s just the way it was and that’s what you did. Just like Barney thinks he has to go into his pen, you do things automatically as well.

For example, when you were a kid, you may have been told not to “talk back” and to just keep quiet about things that were bothering you. These are habits that might have worked to keep you safe and out of trouble when you were young.

Now that you're grown up, you may be finding that these previous strategies are actually causing you problems. In a relationship, not communicating isn't going to work as your partner can’t read your mind. What works when you're a child may not work when you become an adult.

When you decide you need to change your thoughts, your brain may at first feel that it's not a safe thing to do. Lots of practice and years of experience says it’s not. Also, you don’t know to question the thought. It’s a truth for you. The trick is to look at your results and see if your thoughts are the cause. Be willing to question your thinking and ask yourself if there are thoughts that are hindering (妨碍) you. As you are now in a different phase of your life, different strategies may be needed.

小题1:As with the dog Barney, people _______.

A.think in a habitual way

B.enjoy having a car ride

C.usually behave in a friendly way

D.have a good memory小题2:According to the passage, as a kid, one tends to _________.

A.be afraid to make mistakes

B.have the experience of playing with a dog

C.learn much from adults like his/her parents

D.form a habit which can keep his/her out of trouble小题3:In the writer’s opinion, adults should _______.

A.not“talk back”

B.avoid causing any problem

C.change the habit which will bring troubles

D.value their habits formed in their childhood小题4:It can be concluded from the passage that ________.

A.the author’s husband must be good at training dogs

B.childhood is the best time for developing good habits

C.one can change his/her life by changing his/her thoughts

D.you should change all your childhood habits when you grow up

问答题