一、复习目标1．了解空气和水的组成；水、氧气、氢气的物理性质和用途；氧气的工业制法；空气和水的污染与防治等环保常识。2．应用氧气和氢气的化学性质与实验室制取的反应原理。二、知识网络1．车气补充说明：（1）红磷在水面上的钟罩内燃烧产生大量白烟，水面逐渐上升至原 First, review the goal 1. Understand the composition of air and water; the physical properties and uses of water, oxygen, and hydrogen; industrial processes for the production of oxygen; environmental protection knowledge such as air and water pollution and prevention. 2. Apply the chemical properties of oxygen and hydrogen to the principles of reaction prepared in the laboratory. Second, knowledge network 1. Gas supplements: (1) Red phosphorus burns in the bell jar on the water to produce large quantities of white smoke. The water surface gradually rises to the original level.