(6分)“塑化剂”是有毒的邻苯二甲酸酯类物质,邻苯二甲酸(化学式C8H6O4)是

题型:计算题

问题:

(6分)“塑化剂”是有毒的邻苯二甲酸酯类物质,邻苯二甲酸(化学式C8H6O4)是制取邻苯二甲酸酯的主要原料,问:

(1)邻苯二甲酸是由     种元素组成;

(2)邻苯二甲酸分子中碳、氢和氧元素的原子个数比为                

(3)邻苯二甲酸中碳元素的质量分数          (精确到0.1%)。

考点:物质组成元素的质量比化学式的写法和意义物质组成元素的质量分数化合价的求法
题型:计算题

When your pen is broken, you think that’s the end of its life. You throw it away. It then joins tons of other garbage that is becoming a big problem in cities.

Each day, about 10,000 tons of waste is produced in Guangzhou, and 17,000 tons of household waste is produced in Beijing.In other countries, the case is similar.“If you’re like most of us, most Americans, you’re making seven pounds (3.17kg) of trash a day,” US writer Edward Humes told CNN. So, an American makes 102 tons of trash in a lifetime.

If you simply throw away that broken pen, it goes to a landfill(垃圾填埋场) and is buried together with many other trash. To prevent polluting the groundwater, workers cover the trash with soil and keep it dry. And your pen will stay there for a long, long time, without having further use.

But it could have a better destination: the recycling bin.Have you ever noticed the different colors of trash bins in the street? Many cities in China have been running a waste-sorting (垃圾分类) campaign. They divide trash into “recyclable waste” and “unrecyclable waste”.

Recycling waste can save energy, reduce greenhouse gas, and keep space free for the unrecyclable trash.Take your pen as an example. At the recycling factory, its metal parts could be taken out and reused to make other things.But recycling is not enough, experts say. Making less waste in the first place is the way forward.

“The best thing to do is just keep using your stuff for as long as you can,” US writer Adam Minter told Time Out magazine.

小题1:根据短文内容完成句子填空(每空限填一个单词)。

In second paragraph, we can know China is __________ __________ other countries in producing waste.

小题2:根据短文内容完成句子填空(每空限填一个单词)。

Workers cover the trash with soil in order to __________ it __________ polluting the groundwater.

小题3:根据短文内容回答问题。

According to the story, what is the best wayto save energy?

_______________________________________________________________________________

小题4:把短文中画线的句子译成汉语。

_______________________________________________________________________________

小题5:根据短文内容用一个完整的英文句子(限10个词以内)回答问题。

What’s the main purpose of the passage?

_______________________________________________________________________________

题型:计算题

我国近代史上收复新疆、治理边疆的民族英雄是[ ]

A.林则徐

B.左宗棠

C.邓世昌

D.丁汝昌

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如图所示为LC回路中电流随时间变化的图象,规定回路中顺时针电流为正,在t3时刻,对应的电路是图中的(    )

题型:计算题

对于不讲真实姓名、住址,身份不明的现行犯,公安机关可以刑事拘留。

题型:计算题

使用EXCEL将名为2013考试/通话记录利用函数计算出所有通话记录的平均通话时间应在菜单()中选择()进行操作。

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