题干

下列有关分子、原子、离子的叙述正确的是(   )

A:通常状况下气体比金属易压缩,因为分子间有间隔,原子间没有间隔

B:分子、原子、离子三种粒子中原子最小

C:化学变化中分子种类一定改变,原子种类一定不变,离子种类不一定改变

D:在化学变化中原子能集合成分子,离子不能相互作用生成分子

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答案(点此获取答案解析)

C

同类题5

阅读下面短文,从每小题所给的A、B、C、D四个选项中选出最佳选项。

B

    Everyone wants to have a perfect life. But how can we own that? The writer called Brian Tracy tells us some tips:   

    The first goal common to all of us is healthy and energy. We all want to be healthy and fit, to have high levels of energy and to live free of pain and illness. Today, with the quick development of medical science, the quality of our health and fitness, and our lifespan(寿命), is largely determined by design, not by chance. People with excellent health habits are far healthier, have more energy, and live longer and better than people who have poor health habits.

    The second goal that we all have in common is to enjoy excellent relationships, getting along well with the people we like and respect, and who like, love and respect us in turn. Fully 85% of your happiness will be determined by the quality of your relationships(人际关系) at each time, and in each area, of your life. How well you get along with people, and how much they like, love and respect you, has more effect on the quality of your life than perhaps any other reasons.

    The third common goal is to do work that we enjoy, to do it well, and to be well paid for it. You want to be able to get and keep the job you want, to get paid more and promoted(提升) faster. You want to earn as much money as possible at any time, whatever you do.

    The last goal we all have in common is to reach the point in life where you have enough money so that you never have to worry about money again. You want to be completely free of worries about money.