Based on the production process of Sichuan sausage,in a series of processes,such as material preparation,curing,filling and air drying,the chemical principle,material basis and change mechanism behind Sichuan sausage are cracked,the chemical code of its deliciousness and quality is revealed,the relationship between chemistry and life is revealed,and the interest and love for chemistry and life are stimulated.

In the teaching of high school chemistry experiment, cultivating students' critical thinking ability is conducive to students' in-depth understanding of knowledge and improvement of comprehensive ability. However, the current high school chemistry experimental teaching faces the following dilemmas: the design of teaching objectives lacks the elements of critical thinking, the seductive and excitation functions of the experimental teaching situation are often ignored, the challenging questions before and after the experiment are lacking, the experimental inquiry lacks questioning argumentation, and the reflective evaluation of chemical experiments is ignored. In view of these problems, the corresponding cracking path is proposed and demonstrated through cases to cultivate students' critical thinking ability. These solutions mainly include the following aspects: formulating teaching objectives that contain critical thinking, creating experimental teaching situations with “contradictions”, asking inquiry questions and guiding thinking, guiding students to obtain evidence and reasoning carefully, and guiding students to reflect and evaluate in comprehensive judgment.

Based on an existing analytical framework of the nature of science, this paper used the content analysis method to study the changes of the representation of the nature of science in three versions of PEP senior high school chemistry textbooks from a historical perspective. The research found that the number of each dimension of the nature of science in chemistry textbooks increased, and the total number increased significantly, but the distribution of each dimension was uneven. In terms of presentation mode, implicit presentation was always dominant, and the proportion of historical- implicit presentation and historical- explicit presentation was increasing. The proportion of the combination of nature of science and subject content had decreased slightly, but it was still the mainstream. In general, over the past 20 years, Chinese senior high school chemistry textbooks had paid more and more attention to the nature of science, complying with the trend of international chemistry curriculum reform. Finally, some suggestions were put forward based on the research conclusions.

Iodine is an essential microelement for human metabolism and growth. Current chemical textbooks are lack of basic introduction to knowledge of scientific iodine supplementation. Questionnaire survey found that most teachers and students do not have a complete understanding of scientific knowledge of iodine supplementation. Concluded from previous literatures, following points of iodine supplementation are essential: the recommended amount of iodine intake for adult is 120 μg·d^-1; the maximum tolerable amount of intake is 600 μg·d^-1; iodized salt should be consumed in iodine-deficient areas where water iodine is below 40 μg·L^-1, while iodine-free salt is suggested for areas above 100 μg·L^-1; people who regularly ingest iodine-rich food should cut back on iodized salt even in iodine-deficient areas. Therefore, advices on scientific iodine supplementation are put forward in the teaching process and textbook content, so as to improve teachers' and students' cognition level of iodine supplementation and cultivate students' ability to make correct value judgment on related hot social issues.

Taking the 28th question of new curriculum standard paper of the science comprehensive examination of 2023 as an example, this paper reflected and analyzed from the perspective of students' obstacle points, the connection between high school and college, and the examination of students' ability, strengthened the general ideas and methods of organic preparation and put forward some teaching inspiration under the guidance of literacy.

This paper carried out interdisciplinary practical activities with the task of “self-made simple fish pump”. Through market research, data review, sketch design, and fish pump production processes, students can experimence the integration and application of experiential chemistry and multi-disciplinary knowledge, so as to enhance students' ability to solve practical problems. Through the design, production, display, and application of a simple fish pump, this paper builds an activity model that promotes student literacy development through interdisciplinary practical activities.

Exploring activities and learning experiences mainly based on chemical experiments are important ways to learn chemistry. Taking “laboratory production of carbon dioxide” as an example, four teaching stages were designed, including “reaction principle” “generation device” “collection method”, and “verification method”, to model the general ideas and methods of laboratory gas production. In class, three student activities were created to allow them to fully engage in manual and mental experiences; Three experimental explorations were also created to address three cognitive conflicts. In such a classroom, students developed multidimensional and authentic inner experiences such as perception, thinking, emotion, will and values, gradually formed chemical ideas, scientific thinking, questioning spirit, and innovative consciousness, thereby transformed their learning methods.

Taking the ionization of [Co(NH₃)₅Cl]Cl₂ in aqueous solution as the problem scenario, qualitative and quantitative experimental exploration activities were carried out using handheld sensors. Combined with experimental evidence, the exploration of the microstructure of trivalent cobalt ions was initiated, thereby independently constructing relevant concepts of complexes. By creating experimental scenarios such as “adding concentrated ammonia water dropwise to copper sulfate solution until excessive generation of tetra-ammonium copper ions” and “[Co(NH₃)₄Cl₂]Cl presenting purple and green colors”, classroom activities such as association questioning and model building are carried out to promote the transformation of students' learning methods and strengthen the chemical concept of “structure determines properties”.

As an important part of classroom teaching, classroom assessment has a direct impact on the quality of classroom teaching. The process of classroom teaching evaluation has been identified as consisting of four stages: embryonic, initial exploration, in-depth development and innovative development. In this process, the concept of evaluation has shifted from focusing on “knowledge mastery” to focusing on “literacy enhancement”, and the evaluation methods have shifted from “single” to “diversified”. Looking ahead, the main ideas for the future development of classroom teaching evaluation are to keep up with the development of the times, to make use of artificial intelligence technology to promote accurate and diverse evaluation methods, to build a scientific and complete evaluation system based on the characteristics of the subject, and to construct an efficient feedback mechanism.

The picture of high school chemistry teachers based on the internet is of great theoretical and practical significance for a comprehensive understanding of the image of high school chemistry teachers. In 2021 and 2022, the team used Baidu and Bing to retrieve relevant images of high school chemistry teachers. The team also used content analysis to explore the characteristics of the image of high school chemistry teachers on the Internet, as well as the differences in the image of chemistry teachers at home and abroad, it could be found that chemistry teachers in China pay more attention to theory teaching and take an active part in teaching and research activities, but lack of attention to students; hands-on ability and experimental safety. The image of foreign chemistry teachers was more open and practical. On the basis of data analysis in this study, the following reflections are made: the image of chemistry teachers disseminated online can to some extent represent popular public impressions and perspectives; Chemistry teachers need to enhance the practicality of their chemistry classroom in order to fully showcase their image as “scientists”; In addition, diversified online communication is also needed to enrich the public's understanding of the profession of chemistry teachers.

Nature of science is an important component of scientific literacy. Developing students' view of nature of science is a key concern of educational reform in all countries. Teaching is one of the most important aspects of education, and measuring its effectiveness is essential. In this regard, this paper systematically analyzed 20 relevant empirical research papers from 2002 to 2022 through meta-analysis and found that teaching interventions have a high positive impact on students' view of the nature of science (Effect size=1.032 3). Meanwhile, this paper further validated the effectiveness of explicit and historical teaching models for the teaching practice of the nature of science.

On the basis of the conceptual structure map built by Talanquer, this paper draws out the thinking level of senior high school students under the concept of “reaction causality”, and finds that the higher the students' thinking level, the stronger the explanatory power of their answer mode to chemical questions. Students with low thinking level tend to use linear causality or single factor to explain chemical problems, while students with high thinking level tend to use teleology or structured thinking mode to explain chemical problems. Taking the thinking level of senior high school students under the concept of “reaction causality” as the framework, based on the partial credit Rasch model, and using the sequenced multiple-choice items proposed by Briggs, the tool for measuring the thinking level of senior high school students “reaction causality” was developed, and the structural validity and reliability of the tool were good.

With the gradual deepening of conceptual learning, students show different levels of the conceptual understanding and produce the corresponding misconceptions. Based on the Rasch model, this study develops the chemical bonding concept representation inventory, which contains six two-tier test questions and is used to evaluate high school students. The results show that: (1) There are three levels of conceptual understanding of chemical bonding, namely, “structure” “process” and “interaction”. (2) With the rise of the level of conceptual understanding, students will produce the corresponding level of misconceptions. (3)There is inconsistency between students' graphic and linguistic representation level of conceptual understanding. This paper puts forward some suggestions: Teachers should practice the “integration of teaching, learning and evaluation” teaching, carry out “conceptual change teaching” to improve students' conceptual understanding, and use modern information technology to support students to understand scientific concepts and so on.

In order to gain an in-depth understanding of the current situation and problems in the evaluation of chemistry experimental ability of general high school students in Henan province, and to find the focus point of constructing a diversified experimental ability evaluation system, a questionnaire survey was carried out with the chemistry teachers of more than 100 urban and rural general high schools in the province, and a total of 3 897 questionnaires were collected. Correlative analyses were conducted on four aspects: the basic situation of the school, the current status of the school's laboratory equipment configuration, the opening of compulsory experiments for students, and the evaluation of students' experimental ability, in order to understand the problems and analyze the reasons. This paper put forward suggestions such as formulating relevant documents and policies, constructing a scientific evaluation system, and so on, in order to make suggestions for improving the level of evaluation of the experimental ability of chemistry for ordinary high school students in Henan province, and to try to formulate an evaluation scale for the process evaluation of students' experimental ability.

With the combination of Gaussian series software and ChemDraw software, the visualization of electrostatic potential diagrams, multi-information potential energy profiles, and atomic charge distribution diagrams of “aromatic hydrocarbon substitution reactions” is provided to visualize abstract concepts such as the effect of substituents on benzene activity. Through visual graphics, students are trained to learn organic chemistry from the perspective of understanding chemical bonds, interactions between groups, and are motivated to learn chemistry.

The experiments on the bleaching of sulfur dioxide and the dehydrating property of concentrated sulfuric acid are carried out in open containers, which can easily cause the escape of sulfur dioxide and cause environmental pollution. By reconstructing the main text of the textbook and the necessary experiments for students, the self-made H-shaped double test tubes were cleverly utilized to improve the bleaching properties of sulfur dioxide, the acidity, oxidation, reduction properties of aqueous solutions, and the dehydration and strong oxidation properties of concentrated sulfuric acid. The improved experiment has strong operability and obvious phenomena, which can achieve the greening, miniaturization, and integration of the experiment.

This paper described a method for the quantitative analysis of acetylsalicylic acid content in commercial aspirin based on microfluidic thread-based analytical devices in middle school. The method was simple, portable and inexpensive, high strength of substrate material, and ideal experimental time, which was easy for students to understand and operate. With the “determination of aspirin content” as the context, we could strengthen students' grasp of the properties and test methods of organic functional groups, stimulate their interest in experimental research and technological innovation, and cultivate their core literacy of chemistry.

In view of the commonness of teaching content in depth and breadth between high school chemistry contest teaching content and university chemistry specialized basic course education, and the characteristics of attaching importance to the exploration of the nature of matter in the contest teaching, this paper tries to combine the mode of graduate student group meeting with the training of chemistry competition in senior high school, and integrates the classroom of competition training into four links, which are assignment of study task, information collection and arrangement, classroom display and communication, and integration of secondary output, to extend the training to pre-class and after-class, and to practice it in the study of element chemistry. From the feedback after class, the students generally think that their internal drive of study has been mobilized under this mode, learning autonomy and mastery of knowledge significantly improved, but the preparation process takes a lot of energy, reasonable integration with regular classrooms should be considered and applied to specific learning plate.