问题 问答题

A~G各物质间的关系如下图,其中B、D为气态单质.

请回答下列问题:

(1)物质C和E的名称分别为________、________;

(2)可选用不同的A进行反应①若能在常温下进行,其化学方程式为________;

若只能在加热情况下进行,则反应物A应为________;

(3)反应②的化学方程式为_____________________;

(4)新配制的F溶液应加入________以防止其转化为G,检验G溶液中阳离子的常用试剂是________,实验现象为________________。

答案

(1)浓盐酸、四氧化三铁;

(2)2H2O22H2O + O2↑;KClO3

(3)MnO2 + 4HCl(浓) MnCl2+ Cl2↑+ 2H2O   

(4)铁粉,KSCN溶液  溶液变为血红色

①中MnO2作催化剂可知:A为H2O2或KClO3;B为O2;E为Fe3O4

②中MnO2作氧化剂可与C制气体D且C还与Fe3O4反应生成F和G的混合溶液。可确定:C为浓盐酸;D为Cl2;而G为FeCl3、F为FeCl2

(1)物质C和E的名称分别为浓盐酸、四氧化三铁。

(2)进行反应①,若能在常温下进行,A是H2O2其化学方程式为2H2O2 2H2O + O2↑;若只能在加热情况下进行,则反应物A应为KClO3

(3)反应②的化学方程式: MnO2 + 4HCl(浓) MnCl2+ Cl2↑+ 2H2O。

(4)Fe2+有强的还原性,容易被被空气氧化成Fe3+而变质。因此常加入铁粉将变质的Fe3+还原回Fe2+,反应的离子方程式为:2Fe3++Fe=3Fe2+.Fe3+的检验方法是向待测溶液中加入KSCN溶液,若溶液变为血红色,就证明含有Fe3+,或加入NaOH溶液,若产生红褐色的沉淀。就证明含有Fe3+

阅读理解

阅读理解。

     I have an American friend. Her name is Lily. This is a picture of her new school. Look! There are six

 floors (层) in the teaching building. There are fifteen classrooms on every floor. In the school, there are

 3,200 students and 300 teachers. The teachers' offices are behind the classrooms. The dining hall is next

 to the teaching building. Lily often has lunch there. After lunch she often has a talk with her friends. In front

  of the dining hall is a library. It's a good place to read books.

     Lily gets to school at 7:40 a.m. The first class begins at 8:00 a.m. She has four lessons in the morning

  and two in the afternoon. There is a big gym behind the dining hall. After school, Lily likes going

 swimming there.

     The school is big and nice, and Lily likes it very much.

1. How many classrooms are there in the teaching building?

    A. Sixty.

    B. Seventy.

    C. Eighty.

    D. Ninety.

2. What does Lily like doing after school?

    A. Playing basketball.

    B. Going swimming.

    C. Talking with her friends.

    D. Reading books.

3. Where is the school library?

    A. It's behind the classrooms.

    B. It's next to the offices.

    C. It's in front of the dining hall.

    D. It's behind the dining hall.

4. What does the word "begin" mean in Chinese?

    A. 开始

    B. 结束

    C. 休息

    D. 计划

5. What's the best title (标题) of the passage?

    A. My American Friend

    B. Lily's Good Friends

    C. My Favourite School

    D. Lily's New School

单项选择题 案例分析题