试题与答案

实验是学习化学的一个重要途径,探究实验的目的之一是培养同学们的创新思维能力。现有

题型:实验题

题目:

实验是学习化学的一个重要途径,探究实验的目的之一是培养同学们的创新思维能力。现有下列仪器或装置,请回答下列问题:

(1)请写出用D装置制取氧气的一个化学方程式_________________。

(2)草酸(H2C2O4) 固体在浓硫酸作用下发生反应: H2C2O4======CO2↑+CO↑+H2O,若用该反应来制取

CO,制气装置应选                  (填字母);除去其中的CO2可选仪器AC,C中装入的试剂最好是           (填小写字母): a. 烧碱溶液 b. 浓硫酸 c. 澄清石灰水。

(3) 下图为某种“微型”实验装置用它做一氧化碳还原氧化铁的实验时,如果G 处装稀盐酸,H处放少量铁屑,则加热处的现象为                               ;用微型仪器进行实验,除试剂用量极少以外,还可能具有的优点是                          (写1点)。

答案:

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题型:阅读理解

Sports is not only physically challenging, but it can also mentally challenging. Criticism(批评)from coaches(trainers), parents, and other teammates, as well as pressure to win can create too much anxiety or stress for young athletes. Stress can be physical, emotional, or psychological, and research has showed that it can lead to burnout. Burnout has been described as dropping or quitting of an activity that was at one time enjoyable.

The early years of development are critical years for learning about oneself. The sport setting is one where valuable experiences can take place. Young athletes can, for example, learn how to cooperate with others, make friends, and gain other social skills that will be used throughout their lives. Coaches and parents should be aware(realize), at all times, that their feedback(反馈)to youngsters can greatly affect their children. Youngsters may take their parents’ and coaches’ criticisms to heart and find a flaw(缺陷) in themselves.

Coaches and parents should also be cautious(careful) that youth sport participation does not become work for children. The outcome of the game should not be more important than the process of learning the sport and other life lessons. In today’s youth sport setting, young athletes may be worrying more about who will win instead of enjoying themselves and the sport. Following a game, many parents and coaches focus on(pay more attention to) the outcome and find fault with youngsters’ performances. Positive reinforcement should be provided in spite of the outcome. Research shows that positive reinforcement motivates and has a greater effect on learning than criticism. Again, criticism can create high levels of stress(pressure), which can lead to burnout.

小题1:According to the passage sport is positive for young people in that       

A.it can help them learn more about society

B.it teaches them how to set realistic goals for themselves

C.it enables them to find flaws in themselves

D.it can provide them with valuable experiences小题2:According to the passage parents and coaches should       

A.help children to win every game

B.pay more attention to letting children enjoy sports

C.enable children to understand the positive aspect of sports

D.train children to deal with stress小题3:The author’s purpose in writing the passage is        

A.to persuade young children not to worry about criticism

B.to emphasize the importance of positive reinforcement to children

C.to discuss the skill of combing criticism with encouragement

D.to teach young athletes how to avoid burnout

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