基于“大清河盐场”实地观摩考察的初中化学项目式学习——食盐的“旅程”

Project-Based Learning of Junior High School Chemistry Based on Observation and Investigation of“Da-Qinghe Salt Field”:The“Journey”of Table Salt

食盐的工业生产是一个理想的基于实际问题解决的教学素材。盐场的生产环境安全可考察,学生可以完整地了解所有生产环节,与溶液及粗盐提纯的部分关联较为紧密。本课程以"食盐的旅程——从自然界中的盐到餐桌上的盐"为项目主题,开展初中化学"溶液和粗盐提纯"的教学。通过赴大清河盐场考察,针对食盐生产过程中纳潮、晒盐、收盐、洗盐中的问题展开讨论,解释生产过程的核心环节和关键问题,模拟食盐生产过程,自主建构饱和溶液、溶解度等概念,掌握溶解、过滤、蒸发等基本操作技能,建立物质分离的模型。

The industrial production of table salt is an ideal teaching material based on practical problem solving.The production environment in the salt field is safe and can be investigated,students can understand all production links,closely related to the part of the solution and coarse salt purification."The journey of table salt:from salt in nature to salt on the table"as the project theme,carries out the teaching of"solution and crude salt purification"in chemistry course of junior high school.Through the inspection of Da-Qinghe salt field,discussing the problems in the process of salt production,salt washing and salt collection,explaining the core links and key issues of the actual production process,simulating the production process of salt,students construct concepts independently such as saturated solution and solubility,and master basic perating skills(such as dissolution,filtration,evaporation and crystallization),and establish a model of material separation.