一、背景分析多功能瓶在气体制取实验中的使用的相关考题在近几年上海化学中考题中频频出现,学生的得分率较低,多功能瓶的问题常出现在“气体的制取”的情境中的,所以,本学期我上了一节初三化学专题复习课《气体的制取》,对上述问题展开研究。《气体的制取》这节课中,学生最难理解的是启普发生器的作用原理、用多功能瓶进行排空气法收集气体的正确使用方法(是长进短出还是短进长出),还有装置气密性检查的问题等。我发现这些难点,都是与压强有关的,也都与多功能瓶 First, the background analysis Multi-purpose bottles in the gas preparation experiment using the relevant questions in recent years, Shanghai Chemical frequently test questions frequently occur in students score low, multi-function bottle often appear in the gas system Take “situation, therefore, this semester, I went to a third day chemistry class review course” gas system “, to study the above issues. ”Making gas" In this lesson, students most difficult to understand is the principle of Kipp generator, the use of multi-function bottle exhaust method to collect the correct use of gas (is to grow short or short into the long) , As well as the problem of the airtightness check of the device. I found these difficulties are all about the pressure, but also with multi-functional bottle