共查询到20条相似文献，搜索用时 15 毫秒
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在去年高考《理科综合能力测试》的化学试题中,增加新教材知识点的考查比例较大,如：反应热的概念、热化学方程式的书写、卤代烃的化学性质、化学实验方案的设计等。在选择题第13题关于反应热的概念、热化学方程式的书写这个问题中,学生出错较多(该题满分6分,山东抽样统计平均分为 相似文献
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Metal substitution reactions are simple redox reactions. These reactions demonstrate the relative activity and the electrochemical series of metals. In particular, the purpose of this study is to help students comprehend the displacement reaction among, Mg metal and solutions containing Cu+2, Ni+2, Pb+2, Cd+2, Co+2. This study is an important experiment towards understanding reaction kinetics. 相似文献
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本文从共轭关系的角度出发。与酸碱反应相对照。较详细地讨论了氧化还原反应中的共轭关系。 相似文献
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杨玉琼 《贵州教育学院学报》2006,17(2):66-68
利用蔗糖酶作用于蔗糖,使之转化为葡萄糖和果糖的反应,根据反应过程中旋光度的变化追踪反应进程,测定酶的比活性以及米氏常数,从而研究反应条件对酶催化作用的速率的影响。 相似文献
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《International Journal of Educational Research》2001,35(4):427-432
In this chapter, conclusions are drawn and implications are suggested. Of the non-cognitive variables included in the study, the students’ Priorities were the most important in predicting GPA. In general, non-cognitive variables provided important information on admissions. Furthermore, explicit conceptual models, analyzed with relatively sophisticated statistical techniques, are needed to further our understanding of variables directly and indirectly related to college success. 相似文献
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银镜反应实验研究 总被引：2，自引：0，他引：2
银镜反应是中学化学中鉴别醛基存在的典型实验,该实验的条件要求严密,科学性强,对培养学生的科学态度、精神和方法,具有重要意义。本文主要探索生成光亮银镜的实验条件、乙醛与银氨溶液反应的实验条件及操作技术和实验成败关键等。1实验原理银氨络合物在碱性条件下,与醛发生氧化还原反应,把醛氧化成羧酸,而银氨络合物的银离子被还原成金属银,附着在试管内壁形成银镜,故称银镜反应,可以鉴定醛基的存在(1)CH3CHO 2[Ag(NH3)2]OHCH3COONH4 2Ag↓银白色 3NH3↑ H2O(乙酸铵)总之:凡含有醛基的有机物(如:醛、甲酸、甲酸酯、葡萄糖等)都可… 相似文献
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Gopalpur Nagendrappa 《Resonance》2008,13(11):1089-1089
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Richard E. Gallagher 《Studies in Educational Evaluation》1976,2(1):33-34
In examining the Responsive Model, a design for program evaluation, I have approached it, not from the point of view of the evaluation theorist, which I am not, but from the point of view of a faculty member in a health sciences institution who has some responsibility for the evaluation of school programs.My comments and reactions are based not only on Dr. Stake's presentation here, but upon other published and unpublished materials of his. My summary of responsive and pre-ordinate evaluation designs which follow are drawn freely from his work. 相似文献
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