题干

设NA为阿伏伽德罗常数的值,下列说法正确的是(   )

A:1L pH=l的硫酸溶液中含有的H+数目为0.2NA

B:1 mol羟基与l mol氢氧根离子所含质子数均为9NA

C:14 g由N2与CO组成的混合气体中含有的原子数目为2NA

D:标准状况下,2.24 L Cl2溶于水,转移的电子数目为0.1NA

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B

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Crossroads International

    How does crossroads work?

    Crosswords is a resource network. We take goods Hong Kong doesn't want and give them to people who badly need them. We collect those goods and give them out in the welfare agencies in Hong Kong, Mainland China, elsewhere in Asia, Eastern Europe and Africa____

    Who do we help?

    ____ They are grass-root groups who have seen a need and tried to meet it. They can't get the job done without backup, though, so our task is to help them do their task. Our warehouse (仓库) is full of goods, from computers to high chairs, clothing to books, cupboards to dining sets. They send us a list of their needs and we try to match it with the resource we have in stock.

    ____

    Crossroads itself also operates on a low budget. We do not buy the goods we send. They are donated. Similarly, rather than raising funds for freight (货运), we ask transport companies to donate their services____Even our full-time staff work on a voluntary basis.

    What can you do?

    ____ While we receive large quantities of goods and there is never a short supply of requests for them, we are always in need of hands to help sort and prepare them for shipping. If you are volunteering regularly, we can offer work in some of the categories, some of the time.

A. What do we need?

B. How do we operate?

C. So Crossroads is just that: a Crossroads between need and resource.

D. Nobody in our organization receives a salary.

E. One resource that we are always in need of is people.

F. welfare agencies we help do not run on large budgets.

G. All volunteer work is done at our warehouse.