论文部分内容阅读
一般来说,教材的课后习题都是经过编写者精心筛选、有目的设置的,既是对课本知识的补充与延伸,又可为学生训练复习所用,有许多值得挖掘的地方,本文从课后题目出发,并加以拓展,探讨不同课后习题的拓展思路与方法。一、无机推断题:挖掘隐蔽突破口,大胆假设,小心求证课本原题今有甲、乙、丙、丁四种元素,已知:甲元素是自然界中含量最多的元素;乙元素为金属元素,它的原子核外K、L层电子数之和等于M、N层电子数之和;丙元素的单质及其化合物的焰色反应都显黄色;氢气在丁元素单质中燃烧火焰呈苍白色。(1)试推断并写出甲、乙、丙、丁四种元素的名称和
Generally speaking, the after-school exercises of the textbooks are carefully selected and purposely set by the writer. They are both supplements and extensions of textbook knowledge and can be used for student training review. There are many places worth exploring for this article. The topic starts, and it is expanded to explore the ideas and methods for the development of different after-school exercises. First, the inorganic deduction: mining secretive breakthroughs, bold assumptions, carefully verify the original title of the textbook now A, B, C, D four elements, known: A element is the most abundant elements in the natural world; B element is a metal element, The sum of the number of electrons in the K and L layers outside its atomic nucleus is equal to the sum of the electron numbers in the M and N layers; the flame reaction of the elemental and the compound of the element C is all yellow; the hydrogen flame is pale in the single element of hydrogen. (1) Try to infer and write the names of the four elements A, B, C, and D and