The bitter taste is due to the bitter chemicals in the food. In this paper, according to their structures, the common bitter chemicals such as alkaloids, glycosides, polyphenols, terpenes, amino acids and peptides and inorganic salts, were fully introduced.

Textbooks are a crucial medium for the cultivation of students’ ideology. Having the idea of “green development” in textbooks is beneficial for contemporary middle school students to form the concept of sustainable development. Based on content construction evaluation tools of “green development” in textbooks. This paper takes the high school chemistry textbooks of China and America as cases and completes code analysis. The similarities and differences of content, knowledge system and method of constructing in “green development” are revealed by the way of data statistics and case comparison, which reflects the content orientation of “green development” in two sets of textbooks under different cultural backgrounds.

The new high school chemistry textbooks published by the PEP have an overall design of the safety education content. They have outstanding features such as visualization, multiple angles, suitability and conceptuality. We recommend that teachers pay attention to centralized and decentralized introduction, explicit and implicit presentation methods, quantitative regulatory awareness, the content mining, utilization and evaluation of safety education in teaching.

This paper selects the curriculum standards / syllabus of senior high school chemistry in different periods, and makes textual comparison and conceptual analysis on the educational objectives, teaching contents and teaching methods of “chemistry and social issues”. It is found that the curriculum objective has changed from pragmatism to paying attention to students’ core literacy, and the course content has changed from focusing on industrial and agricultural production and national defense construction to the common problems of human society. The teaching ideas are constantly exploring between knowledge system teaching and learning around social issues, which reflects the deepening of educational understanding and the value enhancement of discipline education. Existing experiences are summarized to consider directions of future development with essential issues discussed.

Based on the development of chemical literacy, this paper selected three multiple choice questions in three typical content fields from the chemistry test questions of the National College Entrance Examination in 2019(Ⅰ), and analyzed the measurement objectives of the test questions in three typical content areas: material property and application, chemical experiment and chemical reaction principle. It’s found that weakening the memory requirement of specific knowledge, strengthening the comprehensive ability of effective understanding, analysis and problem solving based on the support of core backbone knowledge had become the value orientation and literacy orientation of the college entrance examinations. While analyzing test questions, teachers should focus more on literacy than on knowledge. Literary-targeted test questions of college entrance examination called for the transformation of classroom teaching, therefore teachers should strengthen their understanding of the connotation and requirements of classroom transformation.

The 2017 high school chemistry curriculum standard adjusts the curriculum structure. Material structure and nature are one of the modules of the optional compulsory courses. The curriculum standard requires students to master not only the specific knowledge about the microstructure of matters, but also establish the method of research and recognize the microstructure of matters, develop the core competence in discipline such as evidence reasoning and model cognition. Based on the visualization software VESTA and the Protein Data Bank (PDB), this study visualizes the structural model of hemoglobin, cuts out its functional unit “heme” and converts its intracellular fractional coordinates into three-dimensional cartesian coordinates for students to build. In the classroom, the general methods and steps of scientists to solve complex molecular structures are restored as much as possible. Students construct the heme atomic position model during project implementation, use the bond length data to judge the bond relationship between atoms, and use the model to explain the mechanism of hemoglobin oxygenation and poisoning. The core competence in discipline such as evidence reasoning and model cognition has been developed.

Taking the school swimming pool disinfection plan as the starting point and the main task, the task is divided into sub tasks and transformed into chemical problems by students. In the study of sodium hypochlorite as the effective component of “84” disinfectant, two-dimensional valence-category diagram of the chlorine containing substances is preliminarily constructed from the perspective of valence and substance class, so that students can have a picture to follow when learning element compounds in the future.

This paper explored the SSI-based instruction of “argumentation the rationality of ‘traffic restriction’ in heavy haze weather” in the teaching of nitrogen and its compounds. By completing the specific teaching procedure: facing the issue to stimulate the original idea, discussing whether there was a relationship between automobile exhausting and haze, discussing whether automobile exhausting was the main cause of haze, making the scientific decision,the students could master the properties of nitrogen and its compounds, establish a thinking method to study the properties and transformation of substances from the perspective of material categories and element valence view, promote the integrative development of multiple dimensions key competencies. After many rounds of teaching improvement, the targeted teaching strategies were drawn on the basis of the process of teaching practice and teaching effectiveness. For example, founding the true scene, the design of driving problems, making the overall arrangement for the three stages: before,during and after class.

In order to effectively implement the core literacy of chemistry, from the perspective of chemistry subject,this study attempted to explore how teacher understands the content of the course.By analyzing experts team’s design process based on grounded theory, this study found that the objects of subject understanding were mainly chemical concepts. In different levels of concept understanding, chemical discipline thinking methods were integrated. Taking the understanding of the core concept of carbonyl as an example, go through the following four steps. (1)Comparing hydrocarbons, the specificity of acetaldehyde was carbonyl. (2)Discovering primitive question based on carbonyl characteristics: how to understand the properties of carbonyl from the perspective of structure. (3)Extracting cognitive perspectives using a comparison-classification logic method: polar multiple bonds. (4)Use hybridization and electronegativity to understand the structural characteristics of carbonyl groups, and develop ideas in combination of macro and micro.

Evidence reasoning is a deep thinking process in which students draw the target concept (new judgment) based on one or several learning materials (known judgments) provided by the teacher, students’ experience and problems. This study constructed the evidence linear process models and cyclic process models that takes “problems, explanations, assumptions, evidence, reasoning, conclusions” as the elements and their relationships by combing and defining the concepts, types of evidence, evidence reasoning process and core elements of evidence reasoning in experimental inquiry teaching. Moreover, this paper uses this analytical perspective and framework to analyze the process of evidence reasoning in the teaching of “ion reaction”, and drew inspiration and suggestions to cultivate students’ evidence reasoning ability based on the six elements of evidence reasoning. To achieve the evidence reasoning process the manifestation of the basic thinking methods in the implementation of the core literacy of the chemistry discipline that implements evidence reasoning and model cognition also provides core reasoning ideas and teaching suggestions for future teaching practice.

“Rational thinking” is one of the key points in core literacy of Chinese students’ development. It is the important content that chemistry curriculum implements core literacy. The spiritual essence of rational thinking lies in the pursuit of the original. Rational thinking is a higher level cognitive skill corresponding to the intuitive experience. It is also the goal and means of science teaching. In chemistry teaching practice, the absence of rational thinking is manifested in the teaching activity lacking the guidance of rational thought, which is prominent in teaching question, teaching model and teaching methods. Therefore, in the design of classroom teaching activities, the cultivation of rational thinking can be carried out from the application of cognitive sequence, thinking mode and thinking method.

The PCK of “hydrogen corrosion and oxygen corrosion” of 46 high school elite chemistry teachers who participated in the “national training program” was investigated by using the localized content representation tool. The results showed that: (1) The PCK of elite teachers consisted of five interrelated components. Among them, knowledge of curriculum, knowledge of learners and knowledge of instructional strategies were relatively rich. Elite chemistry teachers could select subject-specific strategies for chemistry teaching; (2) Regarding orientation toward science teaching, elite chemistry teachers’ awareness of developing and evaluating students’ fundamental beliefs about chemistry and the core literacy in the classroom needed to be strengthened, and the degree of implementation of guiding students’ constructive learning needed to be improved; (3) As to knowledge of assessment, various approaches of assessment were suggested, whereas the formative assessment was not stressed by the teachers. Subsequently, suggestions for the chemistry teacher education in China and chemistry PCK research were provided.

On the basis of reviewing the relevant international literature, through the discrimination of chemistry education research and chemistry research, general education research and other chemistry education activities, this paper discusses the basic characteristics of chemistry education research, the professional requirements of chemical education researchers and the basic requirements that chemical education research design should follow in terms of theoretical basis, research questions and methods. It may be beneficial to improve the understanding of chemical education research, enhance the scientific level of chemical education research in China, and promote the development of chemical education research field.

The basic point of this study is the concept teaching of “intermolecular forces”, and the conceptual cognitive model of handheld technology TQVC is the theoretical basis. By measuring the temperature change curves of 1, 2-propanediol, 1, 3-propanediol and the two mixed alcohols under the same conditions, and comparing the influence of hydrogen bond types on the change of evaporation behavior curve, it was found that the temperature increased first and then decreased. This is not consistent with the phenomenon and conclusions of monohydric alcohol research published by Su Hua-Hong, Qian Yang-Yi et al. Therefore, through the Tetra-Representation model, the following conclusions are drawn: under the same conditions, due to the presence of intramolecular hydrogen bonds and intermolecular hydrogen bonds in some organic compounds, solvation occurs when evaporation takes place with water vapor in the air, and the change of thermal effect is jointly affected by evaporation and solvation.

Based on the idea of STEM education, cooperative learning and project exploration, this paper explored a digital fluorescence colorimetric method determining silver ion based on a smartphone and Color Grab. The method was scientific, novel, accurate and simple. In addition, the application range of colorimetric method was greatly expanded. Smart phones and other digital products have the advantages of universality, systematic coordination and convenience of operation, etc. When carrying out teaching chemistry experiment and extracurricular exploration experiment by fluorescence colorimetry, it can provide new ideas for the reform of chemistry teaching experiment in middle school.

With the help of hand-held technology, the reaction mechanism of sodium bicarbonate and calcium chloride solution was explored by titration. Based on the relevant literature knowledge and experimental comparison, combined with relevant experimental data, the possibility of producing precipitation and gas from sodium bicarbonate solution and calcium chloride solution was analyzed from a quantitative and qualitative perspective.

The reaction of aluminum and sodium hydroxide solution has always been the difficult point of teaching. This paper proved the oxidant of the reaction from a quantitative point of view, and explained the role of hydroxyl ions in the reaction. Based on the different results of the reaction of aluminum with alkaline solution, this study discussed the role of several cations in the reaction.

The research on alternative framework in chemistry mainly includes the diagnosis and analysis of students’ alternative framework, and the development of effective teaching mode or strategy for the conceptual change. Through the analysis of the existing circumstances of relevant research at home and abroad, it provides ideas for the follow-up research of alternative framework.