味精是常用的调味品,某味精由谷氨酸钠(化学式为C5H8NO4Na)和少量的氯化钠

题型:计算题

问题:

味精是常用的调味品,某味精由谷氨酸钠(化学式为C5H8NO4Na)和少量的氯化钠组成,为了测定该味精中谷氨酸钠的含量,进行如下实验:取该味精样品5.50g,溶于蒸馏水中,加入足量的硝酸银溶液(谷氨酸钠与硝酸银溶液不反应),充分反应后过滤、洗涤、烘干、称量,得到沉淀1.35g.计算:

(1)该味精中谷氨酸钠的质量分数.(计算结果精确到1%);

(2)食用该味精3.60g,能为人体提供多少克钠元素?(计算结果精确到0.01g)

考点:化学反应方程式的计算
题型:计算题

Once a great boxer(拳击手), Tom Brown, went to a restaurant for dinner. He put his bag near the door, but he was afraid that someone would take it away. So he got out a pen and a piece of paper and wrote on it, “The great boxer, Tom Brown, left his bag here and he will be back in a few minutes.” He put the paper on his bag and went to have his dinner. When he came back, his bag wasn’t there. But he found a piece of paper on the ground. It said, “A great runner took away your bag, and will not be back.”

小题1:Tom Brown went to the restaurant ________.

A.for his bag

B.to see a doctor

C.for dinner

D.for his pen小题2:Tom Brown was afraid _________.

A.to put down the bag next to the door.

B.he couldn’t find his pen

C.he couldn’t get enough food for himself from the restaurant.

D.thieves(小偷) would take his bag away.小题3:Tom Brown wrote the words on the paper because he ________.

A.was a boxer

B.thought the thief (小偷) would not steal his bag when he read the words.

C.wanted to catch the thief

D.wanted to get to know the runner.小题4:When Tom Brown came back, he _______________.

A.found another piece of paper on the ground.

B.found his bag wasn’t there

C.saw the runner running towards to him

D.both A and B小题5:Which of the following is NOT right?

A.The runner was foolish.

B.The boxer didn’t know the runner at all.

C.The runner was the thief.

D.The runner made a joke on Tom Brown.

题型:计算题
在横线里填上适当的数.
630米=______千米4.6吨=______千克
1.09米=______毫米8.04千克=______克.
题型:计算题

根据短文内容,从下面的A-F选项中选出能概括每一段主题的最佳选项。

A. Review(复习)regularly

B. Make good use of class time

C. Find a good place to study

D. Plan your time carefully 

E. Scan浏览) before you read

F. Take notes in class

Maybe you are an average student with an average intelligent. You probably think you will never be a top student. This is not necessarily so. Anyone can become a better scholar if he or she wants to be.  The following suggestions may be helpful to you:

小题1:

When you plan your week, you should make a list of things that you have to do. Be sure to set aside(抽出) enough time to complete the work that you are normally assigned each week. Of course, studying shouldn't occupy all of your free time. Don't  forget  to  set  aside  enough  time for entertainment, hobbies and relaxation.

小题2:

Look around the house for a good study area. Keep this space, which may be a desk or simply a corner of your room, free of everything, but study materials. No radio or television! When you sit to work, concentrate on the subject!

小题3:

This means  looking  a  passage  over  quickly but thoroughly before you begin to read it more carefully. Scanning a passage lets you preview the material and get a general idea of the content. Scanning will help you double your reading speed and improve your comprehension.

小题4:

Take advantage of class time to listen to everything the teacher says. Really listening in class means less work later.  Taking notes will help you remember what the teacher says.

小题5:

When you get home from school, go over your notes. Review the important points that your teacher mentioned in class. If you do it regularly, the material will become more meaningful, and you will remember it longer.

Develop a good attitude about tests. The purpose of test is to show what you have learned about a subject. Tests do more than just provide grades; they let you know what you need to study more, and they help to make your new knowledge permanent.

题型:计算题

2008年9月27日16时41分至17时许,宇航员翟志刚在太空进行了19分35秒的舱外活动中,飞行了9 165 000 米,成为中国“飞得最高、走得最快”的人。将9 165 000米保留两位有效数字用科学计数法记为[ ]

A.92×105

B.9.2×105

C.9.17×106

D.9.2×106

题型:计算题

下列有关社会主义法治理念的理论渊源和实践基础,不正确的是:( )

A.马克思主义的法治思想是社会主义法治理念的理论基础

B.列宁有关社会主义法治的探索和论述标志着社会主义法治实践的开端

C.社会主义法治理念是马克思主义法治思想中国化的最新成果

D.坚持党的领导、人民当家作主和依法治国的有机统一,是中国特色社会主义法治的根本原则

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