Development of Teaching Materials on Environmental Education in Chemistry

探讨了将学校化学实验产生的重金属废水处理作为环境教育教材引入中小学化学课堂的可能性。结合学校实际情况，建立了铜、银、铝、铁、铬、锰的反应循环。建议将涉及反应循环的化学反应适当地用作化学反应和/或环境教育的教材。介绍了中、高中化学实验中产生的重金属废水的处理方法。为将这些实践作为学生实验的教材，还规定了废水处理的适宜实验条件。此外，还新编写了几种与重金属反应循环有关的教材。从铜的反应循环的发展出发，将碱性铜（II）化合物的沉淀反应作为废水处理和碱性盐化学组成测定的化学实验教材。提出了适合于第二元素系的银反应循环。反应循环中涉及的化学反应也可用于讲授热分解和电解。研制了几种铝罐化学实验教材，并将其引入铝的反应循环中。从铁在空气中氧化反应的角度出发，研究了环境条件对产物羟基氧化铁晶体结构的影响。结果表明，氢氧化铁的结构变形可以作为酸雨的教学材料。

It was examined the possibility of introducing the treatments of heavy metal wastewater produced by the chemical experiments in schools into the secondary elemental and high school chemistry classes as teaching materials of environmental education. Reaction cycles of copper, silver, aluminium, iron, chromium and manganese were established with reference to the practical conditions of the respective levles of school. It was proposed to employ suitably the chemical reactions involving the reaction cycles as the teaching materials of chemical reaction and/or environmental education. It was described the proper treatments of the heavy metal wastewater produced by the chemical experiments in the secondary elemental and high schools. Appropriate experimental conditions for the wastewater treatments were also specified for using the practices as the teaching materials of students' experiments. In addition, several teaching materials relating to the reaction cycles of the heavy metals were newly develped. Concerning the development of reaction cycle of copper, the precipitation reactions of basic copper (II) compounds were utilized as the teaching materials of chemical experiments aiming at the treatment of wastewater and the determination of chemical composition of such basic salts. Reaction cycle of silver appropriate for the secondary element school was proposed. The chemical reactions involved in the reaction cycle can also be used for teaching the thermal decomposition and electrolysis. Several teaching materials of chemical experiments using the aluminium can were developed and introduced into the reaction cycle of aluminium. From a view point of oxidation reaction of iron in air, the influence of the environmental conditions on the crystalline structure of product iron (III) oxyhydroxide were investigated. As a result, it was pointed out that the structural deformation of iron (III) oxyhyroxides can be used as the teaching material in relation to acidic rain.