如何使学生正确记录数据——大学化学有效数字教学改进

科学的数据记录习惯是化学工作者必备的基础素质之一,而大学时期是培养这种习惯的关键阶段。本文从有效数字的重要性出发,针对学生不规范记录数据的现象及原因进行了讨论,提出调动学生的主观能动性使其真正认识到有效数字的重要性是教学改进的入手点,并就此提出相应的改进措施。     

称量和吸量操作中数据有效数字的讨论

理化检验中,通常要用天平和架盘天平称量物质,用玻璃量器吸量液体,并根据其精度,用有效数字准确记录下来。本文将对称量和吸量操作中数据有效数字进行探讨。 1 有效数字新见解 有效数字,是指在理化检验中,实际上能测定到的数字。它是可靠数字和可疑数字的总称。它的位数包括从左端非零数字开始的所有位数,除末尾一位是可疑外,其他各位都是准确的。通常把一般测量数据理解为在可疑数字上有±1或其下一位上有±5的误差。但由于所用天平、架盘天平和玻璃量器的允许误差在末     

统计学在理化检验中的应用第八讲有效数字计算与测量结果的表示

1　有效数字计算记载一个数 ,要求除末位数字有一个单位的误差或其下一位有误差不超过± 5外 ,前面的其它数字都是准确的。即从第一个不为零的数开始至末位数字称为有效数字。例如用万分之一的天平所称得的某样品重 5.2 1 0 3g,其中 5.2 1 0 g都是从所加的砝码标值直接读得的 ,而最后一位数字“3”则是从天平刻度上估计得到的 ,不同的观察者或同一观察者在不同时间 ,它可能被读成“4”或读成“2”,因此最后这位数字“3”是一个可疑数字 ,故 5.2 1 0 3g为五位有效数字。当用千分之一的天平称量该样品时 ,称量结果只能给出四位有效数字。如果…     

浅谈环境水质分析结果的审核工作

对分析结果的有效数字和数据之间的合理性关系问题从理论上进行了研究,为数据审核工作提供科学参考。     

浅论全国高中化学竞赛中的有效数字问题

化学竞赛中,由于计算的复杂性,有效数字的计算有其独特的规则。本文结合近几年来的全国高中化学竞赛试题阐述了其内在的变化规律。     

有效数字在环境监测中的应用

对实验中常用的玻璃量具如单标线吸管、容量瓶、比色管、刻度吸管等进行分析,确定了直读式数据的读数规则及有效位数。如10mL单标线吸管有效数字位数为5位,而10mL刻度吸管随移取溶液体积不同其有效数字位数可能为2,3或4位。分析了环境监测中间接式数据的来源,如标准溶液的浓度、标准曲线的截距、斜率、样品最终浓度等,这些数据应当遵守一定的修约及运算规则,由此确定了间接式数据应当保留合理的有效位数。研究结果可以为环境监测人员开展实验及数据处理提供依据。     

移液管体积该是几位有效数字?

有效数字的概念及运算在分析化学中的重要性是不言而喻的.在滴定分析时,如用0.1008mol·dm~(-3)的NaOH标准溶液滴定HCl溶液,用移液管取25mI HCl溶液于锥形瓶中(这种语言屡见不鲜),滴定管读取消耗NaOH标准溶液的体积为18.65ml.计算HCl溶液的浓度时,就会出现算式18.65×0.1008/25学生直接按此式算出结果得0.07520,但是学生可能根据有效数字运算:     

化学教学中应采用“有效数字”及其计算规则

采用“有效数字”及其计算规则,能起到准确简捷,严密合理的效果。在科学实验中,任一物理量的测量和表示应考虑两点：一是数值的大小,一是准确度如何。物理量数值的大小和准确度通常用“有效数字”表示。大家知道,在化学里,“数”的用途可分为两类。一类是表示不连续物理量数目的自然数,如1、2、3……个水分子,H3PO4化学式中的3、1、4,K2cr2o7的氧化还原当量是其式量的1/6等等。     

AC-1型分析化学计算尺研制成功

AC-1型分析化学计算尺,经有关工厂、大中学校、科研单位试用和鉴定确认:该尺比同长度的普通计算尺在精度上提高一个数量级,在250毫米长的尺度上达到四位有效数字,满足常量组份定量分析计算的要求,     

第三届全国化学教育专题学术研讨会通知(第一轮)

在审稿过程中，发现不少作者对有效数字问题不够重视，数据表达不合理、不精确、不科学、不规范，显得随意、凌乱，这是不符合科学规范的。特整理相关规则，供大家参考，请大家在写文章时注意：     

分析化学有效数字教学中常见问题及分析

Analytical chemistry often involves a large amount of experimental data, and the reliability and accuracy of the experimental results are related to whether the original data can be properly recorded and calculated. In this paper, starting from the importance of significant figures, analyzing the frequently encountered problems related to the significant figures in teaching process, and giving some solutions, we try to help students to learn and master the concept of significant figures, rounding off numerical values, rule of operation and data processing.     

我在“化学拔尖计划”有机化学课堂教学上的三项小尝试

The goal of the Ministry of Education's "Top Talent Training Program" is to train top innovative talents for China and prepare them to be the leading figures in the field of chemical research. This paper summarizes the author's three attempts to reform organic chemistry teaching in the "Top Talent Training Program"; including (1) to present the report of the minireview of organic chemistry as a true academic report; (2) to stimulate students' interest by practical comprehensive structural determination of organic compounds; (3) to create more active learning atmosphere through displaying interesting research stories and new research directions. We also discussed how to stimulate the students' interest in scientific research through these three teaching reforms.     

有机化学双语教学模式改革与探索

给出了适用于本科应用化学及材料化学专业的有机化学双语课程的教学模式和方法。初步解决了目前双语教学语言与专业互不兼顾的问题以及大学英语课程与双语有机化学课程衔接较少的问题。     

基于翻转课堂的大学实验化学教学研究与实践

Experimental chemistry is an important public foundation course for the undergraduate student during their first year at Shihezi University. This paper introduces the teaching status and implementation of the experimental chemistry curriculum. Based on the student activities, this paper firstly constructs flipped learning mode of the experimental chemistry, combining the curriculum resource preparation with online and offline teaching. Secondly, the experimental chemistry curriculum takes deep integration of information technology and classroom teaching as an opportunity. Furthermore, the teaching implementation is carried out by the network teaching platform of Shihezi university. Finally, the student's questionnaire displays that it works well in improving the teaching quality.     

现代分析化学课程教学改革与实践

Modern analytical chemistry is the important professional course for graduate students of analytical chemistry and the related majors. It is the continuation and promotion of knowledge of analytical chemistry course and the key course to improve the scientific research ability of students. The course includes modern separation science, modern electroanalytical chemistry, modern photoanalytical chemistry and advanced analytical chemistry. It is an important guarantee for improving teaching quality to carry out teaching reform of modern analytical chemistry. In the paper, starting from the construction of teaching team, the modern analytical chemistry course group including four courses was set up for the first time. The course contents are reorganized. The teaching methods are optimized and coordinated. The courses are constructed collectively, including reforming the teaching mode and teaching method, editing textbook appropriately and setting up website with a variety of teaching materials. Therefore, the teaching quality can be guaranteed and the disciplinary fundamentals for research work of students can be strengthened.     

提高非高分子专业高分子化学教学效果的探讨

《高分子化学》是研究高分子化合物合成和化学反应的一门科学,是高分子材料专业的一门重要专业基础课,是应用化学和化学工程与工艺专业等非高分子专业的选修课。本文针对应用化学和化学工程与工艺专业等非高分子专业在高分子化学教学中存在的问题与对策进行了积极的探索与实践。结合多年的教学体会,从如何上第一节课、教学内容的取舍、课外活动的开展以及教学方法和手段的改进等方面总结出了一些行之有效的提高非高分子专业高分子化学教学效果的具体措施。     

增加药学专业无机化学"药味"的思考与探索

无机化学是医学院校药学专业学生必修的专业基础课程。为了提高教学质量,增强学生的学习兴趣与专业素养,在药学专业无机化学教学中应强化与药学之间的紧密联系。文章结合教学实践,总结了增加药学专业无机化学"药味"的思考与探索。     

大类培养模式下非化学化工专业有机化学教学改革

针对非化学化工专业学生在学习有机化学时出现的"有机化学无用论、乏味论和繁难论"等现象,对有机化学课程教学的各个环节(包括绪论设置、新课导入、课堂教学内容编排、教学手段、考核方式)进行改革探索,旨在为"促进非化学化工专业有机化学教学改革,提高学生学习效率"提供相应的研究思路和方法.     

计算化学辅助无机化学课堂教学模式的探索

According to the characteristics of inorganic chemistry and in view of the current problems in classroom teaching of inorganic chemistry, the computational chemistry assisted teaching model has been introduced in this paper. The implementation of this innovative model is not only helpful for students to understand the difficult knowledge of inorganic chemistry, but also popularize the practical application of computational chemistry, which provides an opportunity for the establishment of the big data platform of chemistry in colleges and universities.     

物理化学在线开放课程的建设与应用

The construction and characteristics of physical chemistry online open course of Nanjing University have been introduced in this paper, and the application of physical chemistry online open course has been discussed according to the practical experience of online teaching of physical chemistry course during the COVID-19 epidemic period, which could provide a reference for online teaching of physical chemistry.