题干

海洋中有丰富的食品、矿产、能源和药物.如图是从海水中提取某些原料的流程图.

下列有关说法正确的是(   )

A:第①步中除去粗盐中的SO42、Ca2+、Mg2+、Fe3+等杂质,加入的药品顺序为:Na2CO3溶液→NaOH溶液→BaCl2溶液→过滤后加盐酸

B:工业上通过氯碱工业制取金属钠

C:从第③步到第⑤步的目的是浓缩、富集溴单质

D:第②步的反应条件是高温加热

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C

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    Going green seems to be a fad(时尚) for a lot of people these days. Whether that is good or bad, we can't really say, but for the two of us, going green is not a fad but a lifestyle.

    On April 22, 2011, we decided to go green every single day for an entire year. This meant doing 365 different green things, and it also meant challenging ourselves to go green beyond easy things. Rather than recycle and reduce our energy, we had to think of 365 different green things to do and this was no easy task.

    With the idea of going green every single day for a year, Our Green Year started. My wife and I decided to educate people about how they could go green in their lives and hoped we could show people all the green things that could be done to help the environment. We wanted to push the message that every little thing counts.

    Over the course of Our Green Year, we completely changed our lifestyle. We now shop at organic(有机的) stores. We consume less meat, choosing green food. We have greatly reduced our buying we don't need. We have given away half of what we owned through websites. Our home is kept clean by vinegar and lemon juice, with no chemical cleaners. We make our own butter, enjoying the smell of home-made fresh bread. In our home office anyone caught doing something un-green might be punished.

    Our minds have been changed by Our Green Year. We are grateful for the chance to have been able to go green and educate others. We believe that we do have the power to change things and help our planet.