题干

根据以下四个反应:(1)H2S+I2=2H++2I+S¯   (2)H2SO3+2H2S=3S¯+3H2O
(3)2I+Br2=2Br+I2      (4)H2SO3+I2+H2O=H2SO4+2HI
确定Br、I、H2S和H2SO3还原性由强到弱的顺序是

A:H2S>H2SO3>I>Br-

B:Br->I>H2SO3>H2S

C:H2SO3>H2S>Br->I

D:I>Br>H2S>H2SO3

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A

同类题2

阅读理解

    Traveling by bicycle is a very popular means of transportation throughout China. China has a huge population, and it is said that there is at least one bicycle for every two people within the country. Of course, many people in China ride bicycles purely for sport or exercise, but it's also a much more commonly accepted means of everyday transportation, as compared to countries such as the United States.

    If you are living for a long period of time in China, chances are you will want to purchase your own bicycle so that you can use it whenever you want for transportation or just for the enjoyment of riding. Even if you don't use a bicycle for everyday transportation, owning one can be a great way of enjoying some of the trails in the rural areas, just for fun. However, if you are just visiting China, renting a bicycle can be a more convenient choice.

    It is important to choose the correct bicycle for your use. You'll find that in China, the one-speed style of bicycle is extremely popular. These bicycles are great if you want to ride around in the city to see the sights. They are quite comfortable and easy to ride. You can often rent a bicycle for an entire day for around $15.

    However, if you wish to ride on some of the rural paths, a mountain bike style would be a better choice. They are great for different kinds of road surfaces, providing for a safer ride. If you are planning to have a desire to tour and still be able to carry packages with you, then a touring bike would be the best choice. These are generally the most expensive to rent, but are extremely handy for carrying packages and even some of your luggage along with you.

同类题4

现代文阅读

那一年的江水

    四年前,父亲因病去世,我听从母亲的安排,报考了师范。毕业后被分配到一所边陲小村任教。昔日的凌云壮志在繁琐的工作中被消磨得所剩无几。生活条件差,学生们不听话,领导的批评,让我倍感孤寂和怀才不遇。在这里,我找不到倾诉的对象,常一个人骑着自行

    车到不远的江边去看浪花,因为只有浪花才能感受到我的无助和伤感。

    那次是星期天,我没回家,蹬上自行车去看浪花。就是这一次,让我心头豁然一亮,影响了我的一生,甚至改变了我的一生。

    从学校往北走,五分钟便到了江边。江水生生不息地流淌了千百年,江边的泥沙便也日积月累地淤积了千百层,岸边便成了肥沃的土地。可很少有人来这江岸边垦荒播种,倒不是人们粮仓里不缺这些米,口袋里不缺这些钱,而是因为每逢夏季江水都有可能漫到岸边,把庄稼连根拔起,冲得无影无踪,让你起早贪黑白忙乎一场却颗粒无收。因此,江边总是静静的,只听得见浪花的喃喃细语。我放好自行车,慢慢地走在沙滩上。望海鸟飞过,看浪花逝去。我已习惯了这样。

    我稍微抬了一下头,却看见不远处有一片地,禾苗长得枝粗叶大壮实无比,油油的亮光灼得我眼痛,野草疯长得满地都是。更令我感到惊讶的是,在烈日下,竞还有一位瘦矮的农民微曲着身子在锄草。我就这样看着,看着那忙碌的背影发呆。

    也不知过了多久,那位农民在一片空地上坐下来休息。我举目四望,岸滩不远处是一片葱葱茏茏的生机,习习江风不时让这醉人的绿摇着头,或欢笑或歌唱。而空气中也氤氳着江水、泥沙和草儿的清香,偶有一艘帆船向蓝天深处驶去。昔曰对这一切感到窒闷的我竟感染出了些生气来。

    我带着满脑的疑惑同老农聊了起来。我不解地问:“您在这里种庄稼,水涨上来了咋办,那不是白忙了一年吗?”

    老农听后,嘿嘿地笑着说:“谁知道今年水会不会涨上来?我也没去想。你想想看,你要有收成就必须流汗,可流汗了不一定有收成。今年淹了,说不定明年不会淹,希望总是有的嘛!”

    听完老农这番平凡朴实而饱含深厚哲理的话,我脑中像点燃了一团火,像拨亮了一盏灯,让我对前方不再感到迷惑。以前,我总认为我努力工作了一定会得到成绩;我付出了,一定会得到回报。看来,我想错了。老农的话让我明白了对学生的爱是无条件的付出。

    那天,天蓝,云白,心爽。我悠悠地骑着自行车唱着歌回到了学校。之后,讲台上是我深入浅出的讲解,下课时教室里是我悉心辅导的身影。夜晚,星星作伴,我睡得很晚,月亮作证,我起得很早。

    江水那年并没有漫上岸滩,老农的庄稼获得了好收成。而我在人生路上也迈出了很大的一步。