题目

某教师向同学们介绍氨气（NH3）是一种具有还原性的气体，做了如下试验，装置图如下：将氨气通入装有黑色粉末y的玻璃管A中，加热，当黑色粉末全部转化为光亮的红色固体时，U型管B中的白色固体变为蓝色Z，同时集气瓶C中收集到一种无色的气态单质X。   （1）请写出下列物质的化学式x__________y_________z___________ （2）请写出A装置中反应的化学方程式_________________________ （3）请写出B装置中反应的化学方程式_________________________ （4）将少量的镁条与单  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 from 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,such as stairways(楼梯) and fire escapes, but not lifts,and show them to everyone in the family.  From the lower floors of the buildings, escaping through windows is possible. Learn the best way of leaving through windows with the least chance of serious injury(受伤) .  The second floor window is usually not very high from the ground. 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 leak(钻进) 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 hard ground might end in injury. Bushes(灌木丛) and grass can help to break a fall(减弱下降的力量) .(   ) 1. It is important to         .     A. put out the big fire in the burning house    B. jump off a high burning house    C. know the ways to escape from the fire    D. keep the door open(   ) 2. From Paragraph 3，we know that it is possible to escape through the  windows                A. if there are no bushes on the ground    B. if you live on a lower floor    C. if you live on a higher floor    D. if you have no rope(   ) 3. Which of the following escaping ways is NOT right?     A. You can escape through 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 once.(   ) 4. Of course, it isto jump a short way than to stay in a building on fire.     A. safer            B. easier    C. more dangerous    D. more difficult(   ) 5. The best title of the passage is         .     A. Escaping from the Windows    B. Waiting for Help    C. Knowledge on Fire    D. Saving Yourself in a Burning House