问题 填空题

碳有个庞大的家族.

(1)碳单质具有独特的性质和用途,请在以下空格处填写物质名称:

天然存在的最硬的物质______;铅笔芯的主要成分之一______;

(2)碳和部分碳的化合物间转化关系如右图所示.

①物质X的化学式为______.

②在物质的分类中,CO属于______.(填标号)

A.酸   B.碱  C.盐   D.氧化物

③碳酸溶液的pH值______(填“>”或“<”或“=”)7.

(3)最简单的有机物是甲烷,其燃烧的化学反应方程式为:______;生活中用得最多的合成有机高分子材料是______ 等三种.

(4)“低碳经济”的核心是节能减排.从下图中可看出:

①导致空气中二氧化碳气体增加的因素有______(填编号);

②通过海洋消耗二氧化碳的化学反应方程式为:______.

③温室效应的后果是______.

答案

(1)构成金刚石的碳原子形成正八面体结构,是天然存在的最硬的物质;铅笔芯由石墨与粘土混合而制成,因此铅笔芯的主要成分之一为石墨;

(2)①由转化关系图,物质X能与碳酸或一氧化碳实现相互转化,根据二氧化碳的性质及变化规律可推断X为二氧化碳,其化学式为CO2

②一氧化碳由碳、氧两种元素组成,属于化合物中的氧化物;

③碳酸为酸类物质,其溶液呈酸性,pH<7;

(3)甲烷由碳、氢两种元素组成,燃烧时生成二氧化碳和水,反应的化学方程式为CH4+2O2

 点燃 
.
 
CO2+2H2O;合成材料包括塑料、合成纤维、合成橡胶三种有机高分子材料,在生活中都有较为广泛的使用;

(4)根据二氧化碳生成与消耗图片,图中①动植物的呼吸作用、②化石燃料的燃烧、③森林砍伐都导致空气中二氧化碳增加;二氧化碳既能溶于水又能与水反应生成碳酸,因此通过海洋消耗二氧化碳的化学反应方程式为CO2+H2O═H2CO3;温室效应导致地球气温升高而使冰川融化、海平面升高等.

故答案为:

(1)金刚石;石墨.

(2)①CO2;②D;③<.

(3)CH4+2O2

 点燃 
.
 
CO2+2H2O;塑料(或合成橡胶或合成纤维).

(4)①②③;CO2+H2O═H2CO3;气温升高导致冰川融化(合理即可).

阅读理解

Self-esteem(自尊心)is all about how much we feel valued,accepted and thought well of by others---and how much we value,love and accept ourselves.Poeple with healthy self-esteem are able to feel good about themselves,appreciate their own worth,and take pride in their abilities,skills,and accomplishments with others,feel happier,find it easier to deal with low self-esteem may feel as if no one will like them or accept them or that they can’t do well in anything.

Here are some steps that may help improve your self-esteem:

Try to stop     Try to thinking about negative thoughts about yourself.If you’re used to focusing on your shortcomings,start thinking about positive aspects of yourself that outwheigh them .Each day,write down three things about yourself that make you happy.it is good to aim high,but your goals should be within reach.That’s why you should set pratical goals and never expect the impossible.Mistakes are part of learning,so view mistakes as learning opportunities.Accept that you will make mistakes because everyone does.Also, you should recognize what you can change and what you can’t.if you realize that you’re unhappy with something about yourself that you can change, then start today.If it’s something you can’t change(like your height),then start to work toward loving yourself the way you are.Feeling like you’re making a difffference and that your help is valued can do wonders to improve self-esteem.So don’t hesitate to make a contribution.Help a classmate who’s having trouble,help clean up your campus,or volunteer your time in some other way.

Self-esteem plays a role in almost everything you do.It’s never to be late to build healthy positive self-esteem.It takes some work,but healthy self-esteem is an asset you’ll have for life.

小题1:What does the author mainly want to tell us in this passage?

A.Self-esteem plays an important role in life.

B.What self-esteem means

C.How people can improve their self-esteem.

D.What people with healthy self-esteem are like.小题2:The  underlined word “them” in paragagh 3 refers to_____.

A.negative thoughts

B.your shortcomings

C.positive aspects

D.your goals小题3:According to the passage,which of the following can help you improve your self-esteem?

A.Setting high goals.

B.Never forgiving yourself for your mistakes.

C.Changing all the things that make you upset.

D.Lending a hand to a classmate in trouble.小题4:How many ways to improve your self self-esteem are given in this passage?

A.4

B.5

C.6

D.7

单项选择题