题干

钨是我国丰产元素,是熔点最高的金属,广泛用于拉制灯泡的灯丝,钨在自然界主要以钨(VI) 酸盐的形式存在.有开采价值的钨矿石之一白钨矿的主要成分是CaWO4,含有二氧化硅、氧化铁等杂质,工业冶炼钨流程如下:

已知:

①钨酸酸性很弱,难溶于水

②完全沉淀离子的pH值: SiO32− 为8, WO42− 为5

③碳和金属钨在高温下会反应生成碳化钨

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B

    When people ask Kazumi.“What do you do?”,she answers.“I'm a dentist.”Then she watches for the look on their faces.She can see that they are thinking.“I don't like dentists.”She understands how they feel.They are afraid of the drills and pain(钻头和疼痛).

    Kazumi does not want her patients (病人) to feel scared.She takes time to talk to them and make them less afraid.She tells them.“I'm going to be as gentle (温柔的)as I can.I don't like pain myself !”

    When she was a child.Kazumi did not like going to the dentist.She never expected to become one herself.She used to think about becoming a reporter when she grew up.She was interested in talking with different people.Now Kazumi has a different job,but communication is still a big part of her job.She needs to talk with her patients.They need to understand each other.

    Kazumi feels great about her job.She gives three reasons why she is glad to be a dentist.First of all,she knows that she makes her mother happy.Her mother is glad that Kazumi can support herself.She told her daughter, “You won't have to depend on others.It's good for you!”Kazumi also likes working with her hands.A dentist needs great control of very small movements.“I think I have good hands for this kind of work,”she says.Finally, she likes learning new things.As a dentist, she learns from experience and from talking with her boss(老板).Every Friday afternoon, she talks with her boss about her problems at work,and he gives her advice.She has learned a lot from him.

同类题2

为自己设计一个旅行计划,要包括下列问题:1. 想去哪?为什么?2. 想在那儿待几天?3. 怎么去?4. 打算什么时候开始旅行?5. 在这次旅行期间,打算做些什么?

要求:意思连贯、通顺,词数在60—80之间。

提示词语:countryside, air, food and vegetables, environment, fresh, quiet, poor, give, the school things ...

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国家工业和信息化部要求从2009年7月1日起,所有在我国境内生产销售的计算机出厂时都要预装一款名为“绿坝一花季护航”的绿色上网过滤软件。中央财政资金投入4170万元买断“绿坝一花季护航”一年服务,供全社会免费使用。下列说法错误的是(  )
①“绿坝一花季护航”软件是商品,用于交换且有使用价值
②“绿坝一花季护航”软件不是商品,因为不是有形的实物
③“绿坝一花季护航”软件不是商品,因为它是财政资金投入买断的
④“绿坝一花季护航”软件是商品,因为它凝结着无差别的人类劳动

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近几年,由于我市加大环境整治力度,植树造林,不断扩大绿化面积,周围的鸟类越来越多了,这种现象主要体现了( )

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现有仪器烧杯、试管、广口瓶、铁架台、集气瓶、止水夹、酒精灯、玻璃片、燃烧匙、带导气管的橡皮塞,从缺少仪器的角度考虑,下列实验不能进行的是(   )

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