题干

设NA为阿伏加德罗常数的值,下列说法正确的是(      )
①7.8 g Na2O2与足量的CO2反应,转移的电子数为0.1NA
②31g白磷分子中,含有的P—P键数目是NA
③7.8 g Na2S和Na2O2的固体混合物中含有的阴离子数大于0.1×6.02×1023
④在Cu-Zn原电池中,正极产生1.12LH2时,负极产生了0.05 NA 个Zn2+
⑤1mol H2O2含有极性共价键为2NA,含有非极性键为NA
⑥1molFeCl3完全转化为Fe(OH)3胶体后生成NA个胶粒

A:①③

B:③④

C:①⑤

D:②⑥

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C

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    Moving into a new home in a new neighborhood is an exciting experience. Of course, you want to make sure that you become an accepted and valuable part of your new neighborhood. The easiest way to accomplish this is to make sure you conduct yourself as a good neighbor should.____

    Perhaps one of the most important things you can do as a good neighbor is to keep your property(房产) neat, clean, and in good repair. ____By choosing to keep the outside of the home in great shape, you will help to improve the look and feel of the area.

    Second, take the overall appearance of the neighborhood seriously. When going for a walk. Take along a small garbage bag. ____This small act will let your neighbors know that you care about the area.

    ____ If a neighbor is going to be out of town, offer to collect mail and newspapers. If a neighbor suffers an illness, offer to do the grocery shopping. Let them know you are there to help in any way this acceptable, while still respecting the privacy of your neighbor.

    ____By following the basic rules of respecting others, taking care of what belongs to you, and taking pride in the appearance of the neighborhood in general, you will quickly become a good neighbor that everyone appreciates.

A. In general, keep an eye on their property while they are gone.

B.A good neighbor is also one who likes to help out in small ways.

C. Being a good neighbor is more or less about considerate behavior.

D. Sometimes neighbors may go to the supermarket together to do shopping.

E. Should you come across waste paper thrown out of a passing car, pick it up.

F. People tend to lake pride in keeping everything in their street fresh and inviting.

G. Here are a few tips to help you win over everyone in the neighborhood quickly