问题 填空题

按要求写出下列反应式。

(1)金属钠和水反应(化学反应方程式)________________。

(2)实验室加热浓盐酸和二氧化锰的混合物制Cl2(离子反应方程式)________________。

(3)溴乙烷与KOH的乙醇溶液共热(化学反应方程式)____________________。

答案

(1)2Na+2H2O=2NaOH+H2

(2)MnO2+2Cl-+4H+Mn2++Cl2↑+2H2O

(3)CH3CH2Br+KOHCH2=CH2↑+KBr+H2O

完形填空

Kids' health: Four steps for fighting stress

Everybody gets stressed time to time.  1    Some ways of dealing with stress 一like screaming or hitting someone一don't solve (解决) much. But other ways, like talking to someone you trust, can lead you to solving your problem or at least feeling better.

Try taking these four steps the next time you are stressed:

(1) Get support. When you need help, reach out to the people who care about you. Talk to a trusted adult, such as a parent or other relatives.    2    They might have had similar problems, such as dealing with a test, or the death of a beloved pet.

(2) Don't take it out on yourself. Sometimes when kids are stressed and upset they take it out on themselves. Oh, dear, that's good idea. Remember that there are always people to help you. Don't take it out on yourself.     3   

(3) Try to solve the problem. After you're calm and you have support from adults and  friends, it's time to get down to business.        4    Even if you can't solve it all, you can solve a piece of it.

(4) Be positive. Most stress is temporary(暂时的).Remember stress does go away,

especially when you figure out the problem and start working on solving it.

These steps aren't magic, but they do work. And if you can stay positive as you make

your way through a tough time, you'll help yourself feel better even faster.      5     

A.Ask for a helping hand to get you through the tough situation.

B.Notice your friends' feelings and find a way to help them.

C.Different people feel stress in different ways

D.Ah, it feels so good when the stress is gone.E. You need to figure out what the problem is.

F. And don't forget about your friends.

G. Then, find a way to calm down.

单项选择题

阅读以下文字完成题。

现在科学发展的一个重要方面,就是高能物理、基本粒子[a]。这些学问实际上是说明:我们这个世界,到底是怎样的一个世界[b]。

从17世纪的牛顿力学开始,我们研究的是宏观世界[c]。到了20世纪初,发生了两件事,一是量子力学的出现。量子力学研究的是比分子更小的东西。量子力学中分子的大小为10的负8次方厘米[d]。在这种尺度下,牛顿力学[ ],要用量子力学。二是广义相对论的诞生。如果范围扩大到比太阳系还要大,[]银河系像个大盘子,直径为10万光年,对这样大的范围进行研究就要用广义相对论。所以天文学家说,宏观尺度以上还有一个层次叫宇观。这样,科学研究可分为三个层次。

(),研究对象分别是银河星系、山川物体和基本粒子。

随着自然科学的发展,现在发现微观世界中,物体之间有多种作用力。物理学家为了把这些作用力统一起来,就必须考虑一种新的作用力的场,这种场是英国爱丁堡大学希格斯发现的,被称为“希格斯场”。这种场远比基本粒子小,它的大小为10的负34次方厘米。所以,微观中又出现了一个新的概念,这是微观的一个层次,称之为“渺观”。

对上文内容理解正确的一项是()。

A.牛顿在17世纪开创的力学,已不能解决从微观到宇观的研究问题,新的理论已应运而生 

B.量子力学诞生,使人类对客观世界的认识在微观的向度上达到了10的负34次方厘米的层次 

C.“希格斯场”是基本粒子间相互作用力构成的场,它的体积很小,只包括基本粒子,不包括分子 

D.微观世界包括分子,“渺观”指的就是“希格斯场”,它是微观世界中的一个层次,与宇宙无关