问题 填空题

2008年北京奥运会的火炬燃料为丙烷(化学式C3H8),它燃烧时火焰为亮黄色,产物为二氧化碳和水.

(1)下列有关丙烷的叙述正确的是 ______;

①丙烷由碳、氢两种元素组成  ②丙烷由丙烷分子构成  ③丙烷分子由碳、氢两种元素组成  ④丙烷由3个碳原子和8个氢原子组成  ⑤1个丙烷分子由3个碳原子和8个氢原子构成

(2)写出丙烷燃烧的化学方程式 ______.

答案

(1)丙烷(化学式C3H8)的叙述正确的是:①丙烷由碳、氢两种元素组成;②丙烷由丙烷分子构成;⑤1个丙烷分子由3个碳原子和8个氢原子构成;

③④的改正:丙烷由碳、氢两种元素组成. 

(2)根据质量守恒定律,写出反应物和生产物:C3H8+5O2

 点燃 
.
 
3CO2+4H2O

故答为:(1)①②⑤;

(2)C3H8+5O2

 点燃 
.
 
3CO2+4H2O

选择题
阅读理解

阅读理解

                                                     Rising above the names

     I was shopping in the supermarket when I heard a young voice.

     "Mom, come here! There's this lady here my size!"

     The mother rushed to her son; then she turned to me to apologize.

     I smiled and told her, "It's okay." Then I talked to the boy, "Hi, I'm Darryl Kramer. How are you ?"

    He studied me from head to toe, and asked, "Are you a little mommy?"      

    "Yes, I have a son," I answered.

   "Why are you so little?" he asked.

   "It's the way I was born," I said. "Some people are little. Some are tall. I'm just not going to grow any

bigger. " After I answered his other questions, I shook the boy's hand and left.

     My life as a little person is filled with stories like that. I enjoy talking to children and explaining why I

1ook different from their parents.

     It takes only one glance to see my uniqueness. I stand three feet nine inches tall. I was born an a

chondroplasia dwarf (侏儒). Despite this, I did all the things other kids did when I  was growing up.

     I didn't realize how short I was until I started school. Some kids picked on me, calling me names.

Then   I knew. I began to hate the first day of school each year. New students would always stare at me

as I struggled to climb the school bus stairs.

     But I learned to smile and accept the fact that I was going to be noticed my whole life.I decided to

make my uniqueness an advantage rather than a disadvantage. What I lacked in height, I made up for in

personality.

     I'm 47 now, and the stares have not diminished as I've grown older. People are amazed when they

see me driving. I try to keep a good attitude. When people are rude, I remind myself, "Look what else I

have -- a great family, nice friends. "

     It's the children's questions that make my life special. I enjoy answering their questions.  My hope is

that I will encourage them to accept their peers ( a person of the same age, class, position, etc. ),

whatever size and shape they come in, and treat them with respect.

1. Why did the mother apologize to the author?

A. Because the boy ran into the author.

B. Because the boy laughed at the author.

C. Because the boy said the author was fatter than him.

D. Because the mother thought the boy's words had hurt the author.

2. When did the author realize that she was too short?

A. When she grew up.

B. When she was 47 years old.

C. When she began to go to school.

D. When she met the boy in the supermarket.

3.Which of the following word can best replace the underlined word"diminished" ?

A. dismissed    

B. increased      

C. decreased      

D. discriminated

4. How does the author feel about people's stares? 

A. Angry.      

B. Calm.          

C. Painful.        

D. Discouraged.