Preserved egg, as a traditional flavor egg product in China, is a well-known table delicacy at home and abroad. This paper introduced the changes of pH and free alkalinity of protein and yolk, the changes of yolk gel strength and the changes of chemical bonds in yolk, which helped reader understand the formation process of preserved egg gel. The chemical changes of preserved egg flavor were explored through the degradation of precursors, lipid oxidation and Maillard reaction; By analyzing the chemical reactions involved in the changes of protein color and yolk color, the chemical changes in the formation of preserved egg color were decrypted; Finally, the chemical substances that form pine flowers were determined by experimental analysis. By decoding the chemical code of preserved eggs, we could understand the close connection between chemistry and life, and stimulate students' interest in chemistry.

The implementation of the core literacy of chemistry in chemistry education is a realistic problem of current chemistry education and teaching reform in China. Different from traditional exercises, the primitive chemistry problem focuses on the comprehensive quality of students in solving “complex and uncertain practical problems”. It is a new kind of problem that examines students' high level of chemistry core literacy. An in-depth interpretation of the connotation of primitive chemistry problem, a clear understanding of the relationship between primitive chemistry problem and chemistry exercises, and the exploration of the educational value of primitive chemistry problem are conducive to the implementation of the core literacy of chemistry, the promotion of students' systematic thinking, and the guidance of the reform of the evaluation concept of chemical education.

Analogy image takes daily things and life situations as the main content, and helps learners understand scientific concepts through analogy. By analyzing the analogy images of the senior high school chemistry textbooks of people's education press and Shandong science and technology press of 2007 and 2019 editions, it is found that the number of images is small, the range of targets is narrow, the contents presented of images involving the same target of different textbooks are different, the internal structure is simple and easy to understand, explanatory statements are fully expressed. This paper also points out part of analogy failure and puts forward suggestions on textbook compilation, teaching and educational research.

In view of the evaluation system driven by the reform of chemistry curriculum based on core literacy, this paper put forward the design of performance assessment, and would comprehensively analyze the achievement of students' core literacy goals in chemistry. By analyzing the logical relationship between the elements, the goal, the task, the scoring rule and the specific evaluation plan were designed in turn. Taking “preparing a solution with a certain amount-of-substance concentration” as an example, the analysis method of achieving the core literacy goal based on performance assessment was explored, and the requirements of “teaching-learning-evaluation” integration were implemented.

After experimental inquiry and literature research, it's found that the experiments “preparation of simple complexes” by students can be the material for chemistry end-of-term experimental research of senior two, showing the process of proposition. This paper expounds the strategy of setting questions in final examination, which is oriented by extending the classroom experiment and developing the chemistry subject ability.

This paper presents the case of project-based learning results display of “combustion” in junior high school chemistry, and applies the organization mode and implementation strategies of project-based learning results display under the guidance of “learning how to think”. With “I am the designer of the Winter Olympic torch” as the project learning theme and student results display, interactive discussion and evaluation of the design scheme of the Winter Olympic torch as the core learning content of the project, this paper presents the teaching design ideas and teaching practice process of results display in the way of project learning from the seven section of display implementation, so as to provide reference for teachers to carry out project results display practice.

Hou's process for soda production is an ideal teaching material based on actual production analysis. This topic teaching takes “solution” and “salt” related knowledge as the learning content. Through understanding the raw materials of Hou's process for soda production, preparing the raw materials of Hou's process for soda production, exploring the changes in Hou's process for soda production, and understanding the production process of Hou's process for soda production, this topic learning is carried out. This paper also cultivates the ability to solve real problems from multiple perspectives, and focuses on the development of core literacy in chemistry disciplines such as “evidence reasoning and model cognition, scientific spirit and social responsibility”.

This paper expounds the teaching content of “preparation of common gases” in junior high school chemistry, and analyzes the relevant teaching design in the literature. Aiming at the disadvantages of downplaying the knowledge situation, ignoring learning interest and lack of experimental innovation in practical teaching, it proposes to build a real situation, integrate chemistry historical facts and construct systematic cognition,which can promote students to experience the value of disciplines and develop their literacy.

This paper introduces the teaching design idea of “description of extranuclear electron motion state (optional compulsory 2)” in senior high school chemistry. In the teaching,integrate the development history of scientists introducing four quantum number to describe the motion state of extranuclear electrons based on spectral experimental evidence,guide students to develop the atomic structure model, and organically combine it with the cognitive perspective of chemical microcosm. This paper presents relevant teaching records, including stimulating students' cognitive conflicts through spectral experiments; The atomic spectrum is analyzed, and the physical quantity describing the motion state of extranuclear electrons is introduced; Observe the electron cloud and understand the quantized atomic structure model. Through the performance of students, the teaching objectives are evaluated.

The purpose of this study is to help students understand the practical value of the methods and procedures for studying the properties of substances. With the theme of the project “exploring leavening agents”, the students are guided to break down the project into four sub-tasks, including “experiencing the application of leavening agents” “investigating the components of leavening agents” “exploring the working principle of leavening agents” and “self-made leavening agents”, through sharing and questioning, designing research tables data access, personnel interviews, steaming Mantou and other activities emphasize that students experience the problem solving process based on real and unfamiliar situations, and cultivate students' key ability to study the methods and procedures of material properties. Based on the integrated goal of “teaching, learning and evaluation”, a quantitative evaluation table of student performance is designed, and student self-evaluation, group mutual evaluation, teacher evaluation and other evaluations of student learning performance are carried out according to the scoring criteria.

The teaching of “element periodic law” in the selective compulsory stage is carried out with the hot spot of scientific research “hydrogen storage materials” as the carrier. Using the existing “systematic cognitive model of elements and substances” in the compulsory stage, through the two teaching links of selecting elements to prepare metal hydride and analyzing aminoborane, we can understand ionization energy and electronegativity based on cognitive needs, understand double hydrogen bonds, and integrate the new cognition with the existing cognitive model to realize the advancement of cognitive model and the development of systematic thinking ability, cultivate a sense of social responsibility.

The “metal” unit teachingbased on chemical ideas takes knowledge as the carrier, excavates the ideas connotation to be constructed, creates the situation, brings the goal, homework and blackboard design into the overall planning, and consciously guides students to reveal the ideas connotation in the teaching practice. It is helpful to help students understand the ideas and methods behind the specific content, and form structured knowledge and ideas and methods to solve specific problems. Moreover, unit teaching based on chemical ideas can help teachers to shift their focus from knowledge learning to the formation of concept literacy.

Under the background of the new curriculum, the teaching strategies of “mining learning problems under the discipline background” and “developing learning activities with discipline characteristics” under the theme of “molecular structure” are explored to promote the transformation of learning methods, effectively break through the cognitive difficulties and develop the core literacy of chemistry.

Scientific classics are an important carrier of excellent traditional culture. Integrating the rich chemical knowledge contained in them with high school chemistry teaching and learning is conducive to the cultivation of students' comprehensive ability and the inheritance of Chinese excellent traditional moralities. Through a comprehensive analysis of the educational value of Kaogongji, the Liuqi and silk refining and dyeing technology are selected as examples to reveal the chemical principles contained in it, and then put forward the use and expansion of materials and the preparation of test questions. It's significant to guide students to conduct scientific inquiry, cultivate scientific thinking, cultivate patriotic feelings, establish correct values, and implement the cultivation of the core literacy of high school chemistry.

Subject concept plays an important and lasting role in students' learning and development. The concept of element is the core concept of chemistry. The construction of the concept of element helps students form an orderly understanding of the material world and provides a basic framework for the formation of other chemical concepts. In the review stage of senior three, based on the knowledge of elements and compounds and the knowledge of concept principles, students are encouraged to constantly reflect, summarize and refine the factual knowledge of the subject with the help of maze game, and gradually transform the objectively existing knowledge form into the element view in students' minds.

“Ionization equilibrium constant”is a new content in the new textbook. It is one of the important basic constants in high school chemistry and plays an important role in the basic concepts and theories of chemistry. This paper analyzes the background and intention of the introduction of ionization equilibrium constant in combination with the requirements of the curriculum standard, the compilation of teaching materials, and the discipline thinking methods, and expands the application of ionization equilibrium constant while leading teachers to strengthen the understanding of chemistry, and develops students' core literacy of chemistry.

Aiming at the shortcomings of electrochemical corrosion concept teaching, based on the TQVC concept cognitive model of handheld technology digital experiment, a handheld technology digital experiment is designed to promote students' cognition of electrochemical corrosion concept. Using temperature sensor, redox sensor and pH sensor, the temperature curve, redox potential curve and pH curve of aqueous magnesium self heating package working in solution are measured. The working principle of corrosive galvanic cell, corrosion heat generation principle, the role of slow-release homogenizer and embedding agent and the heating effect of various types of lunch boxes are analyzed by means of multiple characterization. The purpose of this study is to help students understand the essence of electrochemical corrosion from the two-dimensional perspective of device and principle, in order to provide reference for daily teaching.

The method in the General High School Chemistry Curriculum Standards to measure protein concentrations was based on the determination of free amino groups (as in amino acids or proteins) by measuring the volume or pressure of nitrogen gas formed by reaction with nitrous acid, which was not applicable to proteins with the nitrogen-containing group in the side chain and auxiliary group. Therefore, this method could not be used to detect the protein content, but could be used to determine the hydrolysis degree of proteins. By comparing various methods to quantitatively determine protein content, such as the Kjeldahl method, UV absorbance method, biuret method, bicinchoninic acid (BCA) method, folin-phenol reagent method, and Coomassie brilliant blue (CBB) binding method, the authors suggested that the biuret method should be adopted in general high school chemistry teaching.

Some common problems in the organic chemistry module of the Olympiad chemistry competition for senior high school students are analyzed. Combining the test questions of the National Chemistry Olympiad, this paper explaines five questions: whether the methyl group has steric hindrance, whether the oxygen cation intermediate is stable, the difference between intermediates and transition states, which is easier to open a five-membered ring or a seven-membered ring, and 1-chlorobicyclo [2.2.1]heptane and 1-chlorobicyclo[2.2.2]octane which is prone to substitution reaction. It is emphasized that the essence of organic modules in the competition is the flexible application of basic knowledge. In order to achieve ideal results, candidates need to consolidate basic knowledge in the learning process and improve their thinking ability.