共查询到20条相似文献,搜索用时 93 毫秒
1.
以“探秘铁肥的合理使用”为主题,开展高中化学“铁及其化合物”的项目式教学。通过完成“确定铁肥的主要成分”“检验铁肥是否变质”“铁肥的合理使用”等3个任务,学生学会不同价态铁元素化合物的转化和检验方法,形成从元素价态和物质类别角度探究物质性质的思路。初步培养了实验探究能力,提升创新意识,发展基于“铁及其化合物价类二维模型建构”的模型认知素养。学生收获了真实新颖、亲身实践、分组合作、交流展示等成就性体验,制作的铁肥保存和合理使用说明书体现了项目式教学的本质特征,实现学习结果的可视性、共享性、交流性。 相似文献
2.
以“氢氧化亚铁的制备”教学设计为例,通过开展专题课,引导学生深入探究氢氧化亚铁制备实验的设计与改进,重点关注学生“科学探究与创新意识”素养水平的发展,并基于具体的测评数据进行反馈评价。 相似文献
3.
基于实证,设计了“氧化还原反应”高三复习课,以“污水处理”为主题,通过创设真实情境,激发生成问题,开展有效活动,引导学生在知识应用中加深对知识的理解,促进知识重构和认识转变,力求实现从虚拟走向真实,从学科走向学生,从经验走向科学,从教学走向教育。 相似文献
4.
5.
以“84消毒液的使用指南”为主题,开展高中化学“次氯酸盐的性质”的教学。学生通过完成“一张图说清消毒剂”“探究84消毒液的漂白效果与酸碱性的关系”“探究84消毒液的漂白效果与光照的关系”“探究84消毒液的漂白效果与温度的关系”“84消毒液与酒精混合会有氯气吗”等5个项目任务,理解了次氯酸盐的性质及漂白原理,培养了学生的文献检索能力、实验探究能力以及发展了学生的高阶思维能力。将文献查阅与学生实验相结合,让学生在真实问题的解决中,完成次氯酸盐的性质等相关知识的内化,是顺利完成本项目教学的关键。 相似文献
6.
7.
以“溶液的形成”为例进行微项目教学实践,选择学生熟悉的护手霜为主题情境,巧妙设计了“原料分散”“微观探秘”“辨识活动”“对比实验”“感知乳化”等系列微项目活动,通过情境不断地设置认知冲突,引导学生反思、修正并最终形成更完善的概念,在环环相扣的探究活动中使学生自主建构结构化的知识。通过制作“护手霜”将“溶解”和“乳化”串联,感知溶液,感受乳化,感悟人与自然、社会的和谐、可持续发展。 相似文献
8.
以“设计过氧化氢使用注意事项标签”为项目主题,开展高中化学“氧化还原反应的应用”教学。学生通过说明书对比发现问题,完成“探究过氧化氢能否与氧化性物质混用”“探究过氧化氢为何不能与还原性物质混用”“探究过氧化氢起消毒作用原理”等3个主项目任务及“寻找日常生活中常见消毒剂”的拓展任务,完成过氧化氢性质的预测及验证,在探究过程中建构并应用价性模型,形成从化合价角度认识物质氧化性或还原性的思路方法,认识氧化还原反应的重要意义。本教学设计为单课时微项目,学生思维的开放度稍弱,可以适当延长课时。 相似文献
9.
介绍了大学有机化学“强理念、重思维、活课堂、共育人、乐钻研”五维度教学新策略的内涵与实践。以线下教学为主,腾讯会议和慕课为辅助,践行“有机化学是科学也是艺术”的教学理念;采用多循环“疑探式”教学方式,辨析亲电试剂和亲核试剂的多样性;注重培养学生多种科学思维的综合运用;强化“文献预习”“练习讲解”“综合作业”“师生互动”等多个教学环节,加深学生对知识的理解与应用,提升学生在课堂中的参与度,着重培养学生的科学思维和人文素养、自主学习与团队合作精神。 相似文献
10.
11.
Areas of fusion and crystallization peaks of K3TaO2F4 and KTaF6 were measured using the DSC mode of a high-temperature calorimeter (SETARAM 1800 K). On the basis of these quantities, considering
the temperature dependence of the calorimeter sensitivity, values of the fusion enthalpy of K3TaO2F4 at the fusion temperature of 1181 K of (43 ± 4) kJ mol−1 and of KTaF6 at the fusion temperature of 760 K of (8 ± 1) kJ mol−1 were determined. 相似文献
12.
V. M. Novotortsev S. F. Marenkin I. V. Fedorchenko A. V. Kochura 《Russian Journal of Inorganic Chemistry》2010,55(11):1762-1773
The results of studying phase equilibria of ternary AIIBIVCV systems have been reported. Physicochemical foundations have been developed for the synthesis of new ferromagnets with Curie
temperatures above room temperature structurally compatible with basic semiconducting materials. Methods of synthesis and
physicochemical properties of manganese-doped AIIBIVC2V ferromagnets have been described. The results of theoretical simulation of magnetic properties have been considered and basic
approaches to the explanation of the emergence of ferromagnetism in AIIBIVC2V doped with 3d metals have been surveyed. The most promising ways to produce and study dilute magnetic semiconductors as spintronics materials
have been presented. 相似文献
13.
Russell G. Baughman Kenneth L. Martin Rajendra K. Singh James O. Stoffer 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):o103-o106
In 2,4‐dihydroxybenzaldehyde 2,4‐dinitrophenylhydrazone N,N‐dimethylformamide solvate {or 4‐[(2,4‐dinitrophenyl)hydrazonomethyl]benzene‐1,3‐diol N,N‐dimethylformamide solvate}, C13H10N4O6·C3H7NO, (X), 2,4‐dihydroxyacetophenone 2,4‐dinitrophenylhydrazone N,N‐dimethylformamide solvate (or 4‐{1‐[(2,4‐dinitrophenyl)hydrazono]ethyl}benzene‐1,3‐diol N,N‐dimethylformamide solvate), C14H12N4O6·C3H7NO, (XI), and 2,4‐dihydroxybenzophenone 2,4‐dinitrophenylhydrazone N,N‐dimethylacetamide solvate (or 4‐{[(2,4‐dinitrophenyl)hydrazono]phenylmethyl}benzene‐1,3‐diol N,N‐dimethylacetamide solvate), C19H14N4O6·C4H9NO, (XII), the molecules all lack a center of symmetry, crystallize in centrosymmetric space groups and have been observed to exhibit non‐linear optical activity. In each case, the hydrazone skeleton is fairly planar, facilitated by the presence of two intramolecular hydrogen bonds and some partial N—N double‐bond character. Each molecule is hydrogen bonded to one solvent molecule. 相似文献
14.
科学史奠基者乔治·萨顿在《科学史导论》第二卷的第一部分对我国宋代酿酒著作《北山酒经》予以了简要描述,出现了“spirits”“distillation”等字样;而《北山酒经》被众多学者认为其描述对象是发酵酒(黄酒)。本文从东西方蒸馏技术和相关著作的文本分析对《科学史导论》中提及的蒸馏技术和蒸馏酒存在的可能性提出了质疑。 相似文献
15.
Areas of fusion and crystallization peaks of K3NbO2F4 were measured using the DCS mode of a high-temperature calorimeter (SETARAM 1800 K). On the basis of these quantities, considering
the temperature dependence of the calorimeter sensitivity, the value of the fusion enthalpy of K3NbO2F4 of (98 ± 6) kJ mol−1 was determined at the fusion temperature of 1257 K. 相似文献
16.
I. E. Zanin K. B. Aleinikova M. M. Afanasiev M. Yu. Antipin 《Journal of Structural Chemistry》2004,45(5):844-848
The structure of Zn3P2 (P 42/nmc, a = b = 8. 0785 Å, c = 11. 3966 Å) was solved and refined to R = 3. 2% in a precision X-ray diffraction experiment (λ-MoK
a, graphite monochromator on a primary beam, 27,496 reflections) . Interatomic distances and bond angles have been determined. The fcc lattice of the structure is built from phosphorus atoms, and the zinc atoms occupy 3/4 of all tetrahedral voids; the structure is described by two equivalent models where 1/4 occupied (by zinc atoms) and 1/4 vacant voids change places. The zinc atoms that occupy the voids following the diamond principle do not change places.Original Russian Text Copyright © 2004 by I. E. Zanin, K. B. Aleinikova, M. M. Afanasiev, and M. Yu. Antipin__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 5, pp. 889–892, September–October, 2004. 相似文献
17.
Aleksandra Yu. Tarasova Yu. V. Seryotkin V. M. Pashkov Ludmila I. Isaenko 《Journal of Thermal Analysis and Calorimetry》2011,104(2):795-796
The temperature dependence of unit cell parameters for monoclinic KPb2Cl5 and tetragonal RbPb2Br5 crystals was studied in the range of 100–298 K. Linear and volume thermal expansion coefficients were determined. 相似文献
18.
19.
L. E. Derlyukova M. V. Vinokurova T. A. Anufrieva 《Russian Journal of Inorganic Chemistry》2008,53(9):1371-1375
The reaction of Bi2O3 + Fe2O3 mixtures with chlorine and SO2 at 250–700°C is studied. At 300–500°C, the degree of bismuth chloride sublimation from the oxide mixture increases in the presence of SO2. Chemical sublimation of FeCl3 occurs after BiCl3 is virtually completely recovered from the solid phase. 相似文献
20.
The results concerning the synthesis, structure and thermal properties of V2O5-MoO3-Ag2O samples in the vanadium rich region of ternary system are presented in the form of quasi-binary phase diagrams in which
at constant V2O5/MoO3 molar ratios, equal 9:1, 7:3 and 1:1, the content of Ag2O was variable. A new ternary phase isostructural with NaVMoO6 has been detected in the investigated system. 相似文献