问题 填空题

(14分)右图为实验室某浓盐酸试剂瓶上的标签,试根据有关数据回答下列问题

(1)该浓盐酸中HCl的物质的量浓度为__________mol/L。

(2)配制250mL 0.1mol/L的盐酸溶液  

应量取浓盐酸体积/mL应选用容量瓶的规格/mL
  
A.用量筒量取所需的浓盐酸的体积,沿玻璃棒倒入烧杯中,再加入蒸馏水,用玻璃棒慢慢搅动,使其混合均匀。

B.将已冷却的盐酸沿玻璃棒注入容量瓶中。

C.用蒸馏水洗涤                       2—3次,洗涤液均注入容量瓶,振荡。

D.继续往容量瓶内小心加水,直到液面接近刻度线1~2cm处,改用               加水,使溶液凹面恰好与刻度相切。

E.将容量瓶盖紧,振荡,摇匀。

(3) 若实验中出现下列现象对所配溶液浓度有什么影响?(填偏高、偏低、无影响)

①将烧杯中溶液转移到容量瓶之前,容量瓶中有少量蒸馏水               

②向容量瓶中转移溶液时不慎有液滴掉在容量瓶外面,则浓度             

③定容时俯视容量瓶刻度线                  

(4)实验室里迅速制备少量氯气可利用以下反应:2 KMnO4+16 HCl ="==" 2 KCl + 2 MnCl2 + 5 Cl2↑ + 8 H2O 此反应不需要加热,常温下就可以迅速进行。

①用“双线桥法” 标明电子转移的方向和数目:

2 KMnO4+16 HCl ="==" 2 KCl + 2 MnCl2 + 5 Cl2↑ + 8 H2O

②用该浓盐酸制得了标况下560mlCl2,则被氧化的HCl为    mol,需要KMnO4的质量      g

答案

(1)    12mol/L     (2分)   

(2)2.1  (2分)    250 (1分)  烧杯(1分)   胶头滴管 (1分)

(3)①无影响   (1分)   ②偏小 (1分)      ③偏大 (1分)

(4) ①(2分)

得到10e

2 KMnO4+16 HCl ="==" 2 KCl + 2 MnCl2 + 5 Cl2↑ + 8 H2O

失去10e

②    0.05 mol(1分)     3.16g(1分)

选择题
单项选择题

D


What are you going to do if you are in a burning house How will you escape Do you know how to save yourself Please read the following passage.
Escaping a fire is a serious matter. Knowing what to do during a fire can save your life. It is important to know the ways you can use and show them to everyone in the family, such as stairways and fire escapes, but not lifts.
From the lower floors of the buildings, escaping through windows is possible, learn the best way of leaving by windows with the least chance of serious injury.
The second floor window is usually not very high from the ground. An average(平均高度的) person, hanging by the finger-tips will have a drop of about six feet to the ground. It is about the height of an average man. Of course, it is safer to jump a short way than to stay in a burning building.
Windows are also useful when you are waiting for help. Be sure to keep the door closed. Or smoke and fire may be drawn into the room. Keep your head low at the window to be sure you get fresh air rather than smoke that may leaked (渗) into the room.
On a second or third floor, the best windows for escape are those that open onto a roof. From the roof a person can drop to the ground more safely. Dropping onto cement(水泥) might end in injury. Bushes(灌木丛) and grass can help to break a fall.

Which of the following escaping way is NOT right ( )

A.You can escape though stairways.

B.You can choose fire escapes.

C.Escape from the windows that open onto a roof.

D.Use a lift to come down at onc