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Introduction to the special issue on Green Chemistry 绿色化学特刊简介
Pub Date : 2022-06-01 DOI: 10.1515/cti-2022-2001
J. Apotheker
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引用次数: 0
SpottingScience – a digital learning environment to introduce Green Chemistry to secondary students and the public spotingscience -数码学习环境,向中学生及市民介绍绿色化学
Pub Date : 2022-06-01 DOI: 10.1515/cti-2021-0025
Anja Lembens, Gerda Heinzle, Alexandra Tepla, N. Maulide, Alexander Preinfalk, Daniel Kaiser, Philipp Spitzer
Abstract Currently, the world is facing climate change, environmental burden, and health aspects caused, among others, by chemical substances spread by humans. In order to preserve or even improve the Earth’s habitat for future generations, the development and use of sustainable technologies are necessary. Additionally, every individual must have knowledge and skills to be able to act in an informed sustainable and responsible way. Neither of these can be achieved without science education that provides appropriate learning opportunities. This paper gives insight into the project SpottingScience whose digital learning environments focus on green chemistry. The learning environments are accessible via QR-Codes in public space at the Campus of the University of Vienna. One can follow the content presented via texts and graphics in a linear way or use provided links to get further information. SpottingScience offers the opportunity for passers-by and secondary school students to get a general idea of green chemistry and its significance for everyday life. We use menthol, a well-known ingredient in several everyday products, as an example to unfold chemical backgrounds, to highlight the necessity to create new and environment-friendly production processes, and to provide an impetus to reflect on one’s own actions while using everyday products.
当前,世界正面临着人类传播的化学物质造成的气候变化、环境负担和健康等诸多问题。为了为子孙后代保护甚至改善地球的生境,必须开发和使用可持续技术。此外,每个人都必须具备知识和技能,能够以知情、可持续和负责任的方式行事。没有科学教育提供适当的学习机会,这两者都无法实现。本文介绍了spotingscience项目,该项目的数字化学习环境侧重于绿色化学。学习环境可以通过维也纳大学校园公共空间的qr码进入。人们可以通过文本和图形以线性的方式来了解内容,也可以使用提供的链接来获取进一步的信息。spotingscience为路人和中学生提供了一个机会,让他们了解绿色化学及其对日常生活的重要性。我们以薄荷醇为例来展示化学背景,强调创造新的环保生产工艺的必要性,并在使用日常产品时提供反思自己行为的动力。薄荷醇是几种日常产品中众所周知的成分。
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引用次数: 1
Simple green organic chemistry experiments with the kitchen microwave for high school chemistry classrooms 简单的绿色有机化学实验用厨房微波炉为高中化学教室
Pub Date : 2022-06-01 DOI: 10.1515/cti-2021-0034
Michael Linkwitz, Robby Zidny, Safwatun Nida, Lea Seeger, N. Belova, I. Eilks
Abstract Microwave systems have been used in organic chemistry since the late 1990s for applications including Microwave-Assisted Organic Synthesis (MAOS). The main advantages of microwave-assisted procedures compared to traditional synthesis methods are the 100- to 1000-fold increase in reaction speeds, higher yields, purer products, and less energy consumption. So far, only a few examples for integrating microwave-induced chemistry into high school chemistry classes have been proposed. This paper presents a set of experiments intended to provide insights into using microwave technology in the context of green, organic chemistry lessons in high school.
自20世纪90年代末以来,微波系统已被用于有机化学,包括微波辅助有机合成(MAOS)。与传统合成方法相比,微波辅助合成的主要优点是反应速度提高100到1000倍,产率更高,产物纯度更高,能耗更低。到目前为止,将微波诱导化学融入高中化学课程的例子很少。本文提出了一组实验,旨在为在高中绿色有机化学课程中使用微波技术提供见解。
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引用次数: 2
Basic concept and application of conducting polymers for environmental protection 环保导电聚合物的基本概念及应用
Pub Date : 2022-05-27 DOI: 10.1515/cti-2021-0041
S. Baharin, R. Rusmin, Kavirajaa Pandian Sambasevam
Abstract Recently, the importance of sustainable environment has been engaged in many science practices and learning. This article intends to provide teachers in secondary school and research beginners with knowledge background on conducting polymers (CPs) for its application in environmental protection studies. A concise and straightforward discussion on the basic concept of CPs and its role as i) sensors for gas pollutants ii) photocatalyst are explained. A general workflow to guide readers in identifying and validating suitable sensors is included. In addition, the article provides a step-by-step guideline to assist readers in performing photocatalytic degradation experiments associated with CPs.
近年来,环境可持续发展的重要性已被许多科学实践和学习所关注。本文旨在为中学教师和研究初学者提供导电聚合物(CPs)在环境保护研究中的应用知识背景。简要而直接地讨论了CPs的基本概念及其作为i)气体污染物传感器ii)光催化剂的作用。一个一般的工作流程,以指导读者在识别和验证合适的传感器包括。此外,文章提供了一个循序渐进的指导方针,以协助读者进行光催化降解实验相关的CPs。
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引用次数: 1
Developing a skills-based practical chemistry programme: an integrated, spiral curriculum approach 开发基于技能的实践化学课程:一种综合的、螺旋式的课程方法
Pub Date : 2022-05-27 DOI: 10.1515/cti-2022-0003
C. D. Campbell, Megan O. Midson, Patrick E. Bergstrom Mann, Samuel T. Cahill, Nicholas J. B. Green, M. Harris, S. Hibble, S. K. E. O'Sullivan, T. To, Lucy J. Rowlands, Z. Smallwood, C. Vallance, Andrew F. Worrall, Malcolm I. Stewart
Abstract Teaching practical laboratory skills is a key component of preparing undergraduate students for future careers in chemistry and elsewhere. In this paper, we present our new strategy to teach practical skills to undergraduate chemistry students. We report a Skills Inventory, a list of the suggested practical skills a graduate chemist should possess; this list was compiled by chemists across the UK. In our new practical course we begin by decoupling the practical skill from the theoretical background, compelling students to first master the basic processes needed to carry out a specific technique. In what we have termed a ‘spiral curriculum’ approach, skills are revisited on multiple occasions, with increasing complexity and greater emphasis on underlying theory. The new course makes links across traditional subdisciplines of chemistry to avoid compartmentalisation of ideas.
教学实践实验技能是准备本科学生在化学和其他领域的未来职业生涯的关键组成部分。本文提出了我国本科化学专业实践技能教学的新策略。我们报告了一份技能清单,一份建议的研究生化学家应该拥有的实用技能清单;这份清单是由英国各地的化学家汇编而成的。在我们新的实践课程中,我们首先将实践技能与理论背景分离,迫使学生首先掌握执行特定技术所需的基本过程。在我们所谓的“螺旋课程”方法中,技能在多个场合被重新审视,越来越复杂,更加强调潜在的理论。新课程将化学的传统分支学科联系起来,以避免思想的划分。
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引用次数: 8
Decision-making factors of female A-level chemistry students when choosing to study a degree in chemistry 女a -level化学学生选择化学学位的决策因素
Pub Date : 2022-05-27 DOI: 10.1515/cti-2021-0030
Rachel Crossdale, Fraser J. Scott, Gemma Sweeney
Abstract Gender issues, and specifically the lack of women in the physical sciences, has been a subject of intense debate for decades. The problem is so acute, that national initiatives have been developed to analyse and address the issues, with some success in STEM, particularly in higher education and also in industry. However, despite this progress, there is little understanding as to why women are less likely to study the chemical sciences in particular. In this research, a survey and interviews were used to find out why female A-level chemistry students choose, or do not choose, to study chemistry at higher education level. Two distinct phases were identified. Firstly, intelligence gathering to understand the location, content, entry requirements, and career options for potential course and institution combinations. Secondly, self-reflection to establish whether, knowing themselves, students feel as though they would be successful on a particular course at a particular institution. These findings align with research into gender imbalance in STEM and Higher Education more broadly, but go beyond this to broaden current debates with a focus on chemistry in particular.
性别问题,特别是女性在物理科学领域的缺乏,几十年来一直是一个激烈争论的话题。这个问题是如此尖锐,以至于各国已经制定了分析和解决这些问题的举措,在STEM领域取得了一些成功,特别是在高等教育和工业领域。然而,尽管取得了这些进展,但人们对为什么女性学习化学科学的可能性更小却知之甚少。在本研究中,通过调查和访谈的方式来了解女性a -level化学学生选择或不选择在高等教育阶段学习化学的原因。确定了两个不同的阶段。首先,收集情报,了解可能的课程和机构组合的地点、内容、入学要求和职业选择。其次,自我反省,以确定,了解自己,学生们是否觉得自己会在某一特定机构的某一特定课程上取得成功。这些发现与STEM和高等教育中更广泛的性别失衡研究相一致,但除此之外,还扩大了当前的争论,特别是化学方面的争论。
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引用次数: 1
Mechanism comics as a task in a written exam in organic chemistry for pre-service chemistry teachers 机制漫画在职前化学教师有机化学笔试中的应用
Pub Date : 2022-05-27 DOI: 10.1515/cti-2021-0035
J. Hermanns, Helen Kunold
Abstract In this paper, we describe and evaluate a study on the use of mechanism comics for writing solutions to a task in a written exam for the course “Organic Chemistry I for Pre-Service Chemistry Teachers.” The students had to design a reaction mechanism for a reaction that was unknown to them and write captions explaining every step of their reaction mechanism. The students’ work was evaluated using the method of qualitative content analysis in four rounds by both authors. The majority of the captions were coded as “descriptive” and only a minority as “causal.” This means that the students mostly described “what” happened, but seldom “why” this happened. Implicit electron movement was also described more often than explicit electron movement. The majority of the captions were technically correct. In summary, the students were capable of designing and describing a reaction mechanism for a previously unknown reaction. The quality of their reasoning could be improved, however. In the new course, the quality of students’ mechanistic reasoning and then especially their explanations of “why” mechanistic steps occur will be given much clearer emphasis.
摘要在本文中,我们描述并评价了一项关于在“职前化学教师有机化学I”课程的笔试中使用机制漫画来写答案的研究。学生们必须为一个他们不知道的反应设计一个反应机制,并写下说明说明他们的反应机制的每一步。两位作者采用定性内容分析的方法对学生的作业进行了四轮评估。大多数标题被编码为“描述性”,只有少数被编码为“因果性”。这意味着学生们大多描述“发生了什么”,但很少描述“为什么”发生了。隐式电子运动也比显式电子运动更常被描述。从技术上讲,大多数标题都是正确的。总之,学生们能够设计和描述一个以前未知反应的反应机制。然而,他们推理的质量还有待提高。在新课程中,学生的机械推理的质量,特别是他们对“为什么”机械步骤发生的解释将得到更加明确的重视。
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引用次数: 2
Efficiency of reversible reaction: a graphical approach 可逆反应的效率:图解法
Pub Date : 2022-05-16 DOI: 10.1515/cti-2022-0004
I. Novák
Abstract We describe simple, quantitative, graphical approach to solve chemical equilibrium problems and quantify how far the reversible reaction advances upon reaching equilibrium state at a given temperature. The same approach also gives the change in reaction advancement ratio (reaction efficiency; % completion of reaction) upon perturbation of equilibrium state by changing equilibrium concentrations (moles) of reactants or products. The approach is based on plotting two polynomial functions which represent how the numbers of moles of reactants and products vary with the advancement of reaction. The point of intersection of the two polynomial curves (functions) gives advancement ratio for a reversible reaction at equilibrium (χ e). In comparison, Le Chatelier’s principle is qualitative and tells us that equilibrium concentrations (moles) of products will increase (or decrease) once concentrations of reactants are made larger (or smaller), but does not predict the change in advancement of reversible reaction upon re-establishing the equilibrium state. In other words, it does not specify whether after perturbation the conversion to products will result in higher or lower reaction efficiency. Our quantitative approach is complementary to the qualitative Le Chatelier’s principle and is applicable to any single-equation equilibrium system. It can also be an alternative to ICE tables.
摘要:我们描述了一种简单的、定量的、图形化的方法来解决化学平衡问题,并量化了可逆反应在给定温度下达到平衡状态后的进展程度。同样的方法也给出了反应推进比(反应效率;通过改变反应物或生成物的平衡浓度(摩尔)来扰乱平衡状态。该方法是基于绘制两个多项式函数来表示反应物和生成物的摩尔数随反应进展的变化情况。两个多项式曲线(函数)的交点给出了可逆反应在平衡状态下的推进比(χ e)。相比之下,勒夏特列原理是定性的,它告诉我们,一旦反应物浓度变大(或变小),产物的平衡浓度(摩尔)会增加(或减少),但不能预测可逆反应在重新建立平衡状态后的推进变化。换句话说,它没有规定扰动后转化为产物的反应效率是高还是低。我们的定量方法是对定性勒夏特列原理的补充,适用于任何单方程平衡系统。它也可以替代ICE表。
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引用次数: 0
H-atom and O-atom methods: from balancing redox reactions to determining the number of transferred electrons h原子和o原子方法:从平衡氧化还原反应到确定转移电子的数量
Pub Date : 2022-04-18 DOI: 10.1515/cti-2021-0028
Pong Kau Yuen, C. M. Lau
Abstract Defining and balancing redox reaction requires both chemical knowledge and mathematical skills. The prevalent approach is to use the concept of oxidation number to determine the number of transferred electrons. However, the task of calculating oxidation numbers is often challenging. In this article, the H-atom method and O-atom method are developed for balancing redox equations. These two methods are based on the definition of redox reaction, which is the gain and loss of hydrogen or oxygen atoms. They complement current practices and provide an alternate path to balance redox equations. The advantage of these methods is that calculation of oxidation number is not required. Atoms are balanced instead. By following standard operating procedures, H-atom, O-atom, and H2O molecule act as artificial devices to balance both inorganic and organic equations in molecular forms. By using the H-atom and O-atom methods, the number of transferred electrons can be determined by the number of transferred H-atoms or O-atoms, which are demonstrated as electron-counting concepts for balancing redox reactions. In addition, the relationships among the number of transferred H-atom, the number of transferred O-atom, the number of transferred electrons, and the change of oxidation numbers are established.
定义和平衡氧化还原反应需要化学知识和数学技能。常用的方法是用氧化数的概念来确定转移电子的数目。然而,计算氧化值的任务通常是具有挑战性的。本文发展了h原子法和o原子法来平衡氧化还原方程。这两种方法都是基于氧化还原反应的定义,即氢原子或氧原子的得失。它们补充了当前的实践,并提供了平衡氧化还原方程的替代途径。这些方法的优点是不需要计算氧化值。原子是平衡的。通过遵循标准操作程序,h原子、o原子和H2O分子作为人工装置来平衡分子形式的无机和有机方程。通过使用h原子和o原子的方法,可以通过转移的h原子或o原子的数量来确定转移电子的数量,这被证明是平衡氧化还原反应的电子计数概念。此外,还建立了转移h原子数、转移o原子数、转移电子数与氧化数变化的关系。
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引用次数: 2
Students’ and teachers’ perceptions for composition of ionic compounds 学生和教师对离子化合物组成的看法
Pub Date : 2022-04-06 DOI: 10.1515/cti-2021-0032
A. W. Wisudawati, H. Barke, Abayneh Lemma Gurmu, S. Agung
Abstract We investigate how chemistry-teacher students and teachers interpret chemical equations regarding the sub-microscopic level of solid ionic salts and their solutions. Addressing participants’ skills in making sense of chemical formulas might significantly influence students’ conceptual understanding: ionic salts formulas like Na2CO3(s), CaCO3(s), MgO(s) were established in the questionnaire. A coding system used to reveal participants’ reasoning correspond to their misconceptions. The enrolled participants were 101 undergraduate chemistry education students from Indonesia and Ethiopia and 24 chemistry teachers from Indonesia and Tanzania. Our results showed students’ and teachers’ difficulties in figuring out the involved ions of provided salts and interpreting the chemical formulas. Consequently, general chemistry learning should provide better fundamental knowledge on the submicroscopic level based on involved particles like atoms, ions, and molecules. It would also be helpful to introduce an appropriate sequence of historical ideas to find the existence of atoms, ions, and molecules.
摘要:我们研究了化学教师学生和教师如何解释亚微观水平的固体离子盐及其溶液的化学方程。解决参与者对化学式的理解能力可能会显著影响学生的概念理解:在问卷中建立了Na2CO3(s)、CaCO3(s)、MgO(s)等离子盐的公式。一个编码系统用来揭示参与者的推理与他们的误解相对应。被招募的参与者是来自印度尼西亚和埃塞俄比亚的101名本科化学教育学生以及来自印度尼西亚和坦桑尼亚的24名化学教师。我们的研究结果表明,学生和教师在确定所提供的盐的参与离子和解释化学式方面存在困难。因此,普通化学学习应该在亚微观层面上提供更好的基础知识,这些知识是基于原子、离子和分子等相关粒子的。引入适当的历史观念序列来发现原子、离子和分子的存在也会有所帮助。
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引用次数: 2
期刊
Chemistry Teacher International : best practices in chemistry education
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