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1987年11月,在全国范围内举行了一次高二学生化学竞赛。本刊特公布这份赛题,一是作为历史资料;二是为引起各界的注视和研讨,推动化学竞赛的发展。据有关人士说:这种全国高二学生化学竞赛,今后要年年搞,一年一度;赛题的知识水平,就其基本内容,不超过高二化学的大纲和进度;但赛题要求参赛音有较高的智力水平。简言之,竞赛是智力的竞赛,不是知识的竞赛。或者说,竞赛对参赛者的知识要求是一般的,普遍可及的,而对参赛者的智力要求是特殊的,但也不是高不可攀的。诚然,不能说下面公布的这份赛题已充分体现了上面的命题原则,但它是努力地去体现这一原则的。以第11题为例。解此题所需的化学知识并不超过中学化学的教学水平:①浓硫酸有吸水性;②浓盐酸有挥发性;③若将浓盐酸滴入浓硫酸,必将出现两个相反的热效应:一方面,浓硫酸与水反应将放热;另一方面,氯化氢挥发将吸热,这跟将纯水滴入浓硫酸的热效应将有差别;④此题所列的其他试剂无一可发生学生已学过的氧化还原反应并放出某种气体;⑤所谓“纯净的”气体自然包含着连水蒸气也不应作为杂质;⑥氯化氢极易溶于水,为制得纯 HCl 气体绝不应用水溶液去洗涤它;……如果说,这些知识超出了学生的认识范围,绝不是各个知识点本身而是它们的综合。而综合知识,从本质上讲,是智力,不是知识本身。尽管该题的干燥氯化氢气体的制法本身正是实验室少量 HCl 气体制法的常规方法,但中学化学,甚至大学化学里都未提及,这或许是教材有些问题,但似乎也不必要求凡是有用的教材里都必须讲到。出题者或许正是考虑到应当取大家不熟悉的命题来作为赛题对所有参赛者才是公平合理的。参赛者及其指导者们不应当去补知识,若是以这种想法来准备竞赛,恐怕是补不完的。重要的是将已学的知识、概念、原理综合起来,运用于新的未知的场合,以得出正确的结论。
In November 1987, a high school student chemistry competition was held nationwide. This issue is specifically published in this magazine. First, it is used as historical data. Second, it is to arouse the attention and discussion of all walks of life and promote the development of chemical competition. According to relevant sources, this national high school student chemistry competition will be held year after year, once a year; the level of knowledge of the competition title should not exceed the outline and progress of the senior year chemistry; Higher intelligence level. In short, the competition is a contest of intelligence, not a contest of knowledge. Or, the knowledge requirements of contestants for contestants are general and universally accessible, and the intelligence requirements for contestants are special, but they are not unattainable. Admittedly, it cannot be said that the title published below fully embodies the above propositional principle, but it is an effort to embody this principle. Take the eleventh example as an example. The chemical knowledge needed to solve this problem does not exceed the teaching level of middle school chemistry: 1 Concentrated sulfuric acid has water absorption; 2 Concentrated hydrochloric acid has volatility; 3 If concentrated hydrochloric acid is added dropwise to concentrated sulfuric acid, there will be two opposite thermal effects: On the one hand, concentrated sulfuric acid reacts with water to exotherm; on the other hand, hydrogen chloride volatilizes to absorb heat, which is not the same as the thermal effect of dipping pure water into concentrated sulfuric acid; 4 none of the other reagents listed in this question will occur. The oxidation-reduction reaction that has been learned and emits a certain gas; 5 so-called “pure” gas naturally contains water vapor and should not be used as impurities; 6 hydrogen chloride is easily soluble in water, so pure HCl gas is not used to obtain aqueous solution Go to wash it; ... If you say, this knowledge is beyond the students’ understanding, it is not the knowledge points themselves but their synthesis. Comprehensive knowledge, in essence, is intelligence, not knowledge itself. Although the method for producing dry hydrogen chloride gas in this case is itself a routine method for making a small amount of HCl gas in the laboratory, it is not mentioned in middle school chemistry or even university chemistry. This may be a problem in teaching materials, but it does not seem to require that everything be Useful teaching materials must be mentioned. The questioner may just consider taking the proposition that everyone is not familiar with as a problem for all contestants. Participants and their mentors should not make up for the knowledge. If this idea is used to prepare for the competition, I am afraid it will not be able to make up for it. It is important to integrate the knowledge, concepts, and principles that have been learned and apply them to new and unknown occasions to arrive at a correct conclusion.