问题 问答题

化学方程式能够很直接形象的表示化学反应的过程与特征的一种符号,书写化学方程式是我们必须掌握一项基本技能.请按照要求完成下列方程式.

Ⅰ,生活中很多现象和原理都可以用化学反应来解释:

(1)写出 泡沫灭火器反应原理的离子方程式:______.

(2)氨气是重要的化工原料,请写出 实验室制氨气 的反应方程式:______.

Ⅱ,某一反应体系有反应物和生成物共六种物质:N2O、FeSO4、Fe(NO33、HNO3、Fe2(SO43和H2O.写出该反应的化学方程式:______.

Ⅲ,有一些反应,表面上似乎违背了反应的基本原理,事实上他们是完全符合反应基本原理的.请完成下列反应:

①写出两种弱酸溶液混合反应后,溶液的酸性减弱 的化学方程式______.

②写出一种弱酸溶液与一种盐溶液混合发生复分解反应,生成强酸 的离子反应方程式______.

答案

Ⅰ、(1)泡沫灭火器反应原理是硫酸铝和碳酸氢钠溶液混合产生二氧化碳和氢氧化铝沉淀,反应的离子方程式为:Al3++3HCO3-=Al(OH)3↓+3CO2↑,

故答案为:Al3++3HCO3-=Al(OH)3↓+3CO2↑;

(2)实验室制取氨气是用氢氧化钙和氯化铵固体加热反应生成,反应的离子方程式为:2NH4Cl+Ca(OH)2

  △  
.
 
CaCl2+2NH3↑+2H2O,

故答案为:2NH4Cl+Ca(OH)2

  △  
.
 
CaCl2+2NH3↑+2H2O;

Ⅱ、一反应体系有反应物和生成物共六种物质:N2O、FeSO4、Fe(NO33、HNO3、Fe2(SO43和H2O,硝酸做氧化剂被还原为N2O,能做还原剂的化合价升高,FeSO4被氧化为硫酸铁

硝酸铁,依据氧化还原反应的电子守恒和反应的原子守恒书写配平化学方程式:24FeSO4+30HNO3=8Fe(NO33+8Fe2(SO43+3N2O+15H2O,

故答案为:24FeSO4+30HNO3=8Fe(NO33+8Fe2(SO43+3N2O+15H2O;

Ⅲ①两种弱酸溶液混合反应后,溶液的酸性减弱,依据所学弱酸混合发生氧化还原反应:还原性酸为H2S,氧化性弱酸为H2SO3;化学方程式为:2H2S+H2SO3=3S↓+3H2O,

故答案为:2H2S+H2SO3=3S↓+3H2O;

②一种弱酸溶液与一种盐溶液混合发生复分解反应,生成强酸,依据复分解反应条件分析:硫酸铜和氢硫酸反应生成硫化铜沉淀,难溶于强酸,反应的离子方程式为Cu2++H2S=CuS↓+2H+,故答案为:Cu2++H2S=CuS↓+2H+

阅读理解

 阅读理解。

                                   To Give up or Not to Give up as Class Monitor?

Dear Brad, 

      In about 3 months, I will take a very important test. If I pass the test with good grades, I can get to the

10th grade and choose a good school to study in. Now I am trying my best to achieve this. At the same time, I'm the monitor in my class, which means I should do lots of things for my class. ① I am so busy with my

school-work and duties as monitor that I don't have enough time to keep a balance between them. Gradually

I become lazy. ② The other day, my head teacher told me that she was disappointed in my poor performance

as class monitor. Her words really discouraged me. 

     What should I do now, to give up or not to give up as class monitor? I must do my best in school because

how well I do will influence where I go after this school year is over and it can affect the rest of my life. Being

class monitor is also a valuable learning experience because my teacher trusts me to be a good leader. ③ I

don't want to go to my parents for suggestions, for they will get worried about me. Can you tell me how to

choose?

                                                                                                                                                Yours, 

                                                                                                                                                Gates

1. 根据①处内容,完成下面的句子。(每空一词)

    I am _______ busy with my school-work and duties as monitor _______ have enough time to keep a

balance between them. 

2. 根据②处内容,完成下面的句子。(每空一词)

     The other day, my head teacher said to me, " _______ _______ disappointed in your poor performance

as class monitor." 

3. 将③处翻译成汉语。

    _____________________________________________________________________________________ 

单项选择题