论文部分内容阅读
一、知识概要 (一)水 1.水的性质:①水是没有颜色、没有气味、没有味道、透明的液体。②水能溶解某些物体。 2.水的三态变化和水在自然界里的循环:水有三种形态,即固态、液态和气态,在一定条件下,三种形态能够互相变化。在自然界里水的三态不停地发生变化,造成云、雾、露、霜、雪、雨等各种天气现象,形成自然界里的水的循环。促使水在自然界循环的力量主要来自太阳的热和地球引力。 3.水的净化:把不纯净的水变成纯净水的过程
First, a summary of knowledge (A) of water 1. The nature of water: ① water is no color, no smell, no taste, transparent liquid. ② water can dissolve certain objects. 2. Tristate changes in water and water circulation in nature: There are three forms of water, solid, liquid and gas, under certain conditions, the three forms can change each other. In nature, water constantly changes in the three states, resulting in clouds, fog, dew, frost, snow, rain and other weather phenomena, forming the water cycle in nature. The forces that cause water to circulate in nature come primarily from the heat of the sun and the earth's gravity. 3. Water Purification: The process of converting impure water into pure water