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问题 选择题

工业用盐亚硝酸钠（NaNO2）有毒，其外观与食盐极为相似，在隔绝空气和强热条件下，亚硝酸钠能分解放出一种红棕色气体，该气体可能是（　　）

A．N2

B．CO

C．NO2

D．O2

答案

A、氮气为无色无味的气体，不符合题意，故A错；

B、一氧化碳没有气味且在亚硝酸钠中不含碳元素，所以不能生成一氧化碳，故B错；

C、二氧化氮为红棕色气体，且在硝酸钠中含有氮元素和氧元素，所以可能是二氧化氮，故C对；

D、氧气是一种无色无味的气体，故不符合题意，故D错．

故选C．

单项选择题

Children are a relatively modem invention. Until a few hundred years ago they look like adult, wearing grown-up clothes and grown-up expressions, performing grown-up tasks. Children did not exist because the family as we know it had not evolved.
Children today not only exist; they have taken over in no place more than in America, and at no time more than now. It is always Kids Country here. Our civilization is child-centered, child-obsessed. A kid’s body is our physical ideal. In Kids Country we do not permit middle-aged. Thirty is promoted over 50, but 30 knows that soon his time to be overtaken will come.
We are the first society in which parents expect to learn from their children. Such a topsy-turvy situation has come to abort at least in part because, unlike the rest of the world, ours is an immigrant society, and for immigrants the only hope is in the kids. In the Old Country, that is, Europe, hope was in the father, and how much wealth he could accumulate and pass along to his children. In the growth pattern of America and its ever- expanding frontier, the young man was ever advised to GO WEST; the father was ever inheriting from his son. Kids Country may be the inevitable result.
Kids Country is not at all bad. America is the greatest country in the world to grow up in because it is Kids Country. We not only wear kids clothes and eat kids food; we dream kids dreams and make them come tree. It was, after all, a boys’ game to go to the moon.
If in the old days children did not exist, it seems equally true today that adults, as a class, have begun to disappear, condemning all of us to remain boys and girls forever, jogging and doing push-ups against eternity.

It was suggested but not stated that the American West is the place where ______ .

A．young people are reluctant to go
B．people may possibly get wealthy
C．it is more interesting to settle
D．the old people’s dreams can be realized
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判断题

残疾人参加合唱队或者登山俱乐部可以教会残疾人自制，并且享受成功合作的乐趣。
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