题干

现有一包铝热剂是铝粉和氧化铁粉末的混合物,在高温下使之充分反应,将反应后的固体分为两等份,进行如下实验(计算pH时假定溶液体积没有变化):
①向其中一份固体中加入100mL 2.0mol·L1的NaOH溶液,加热使其充分反应后过滤,测得滤液的pH=14;
②向另一份固体中加入100mL 4.0 mol·L1的HCl溶液,使固体全部溶解,测得反应后所得溶液中只有H+、Fe2+和Al3+三种阳离子且pH=1。
则②产生气体的体积(标准状况)为(   )

A:2.352L

B:2.448L

C:2.688L

D:2.856L

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D

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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.