物质性质是学生学习物质、认识世界、学习科学方法及进行实验探究和社会实践的重要内容支撑，承载全面落实发展学生核心素养的功能。而学生必做实验是学生学习化学和进行探究活动的基础与保障。以“化学必做实验”为载体，深度开展“物质性质探究”，不仅能培养学生基本的化学实验技能，还能帮助学生形成物质性质探究的思路与方法，从而发展其探究能力。在此研究背景下，本研究首先根据《义务教育阶段化学课程标准（2022 版）》主要分析“科学探究与化学实验”、“物质性质与应用”两大学习主题相关内容，然后查阅有关“实验探究能力”的文献，分析实验探究能力的发展、教学策略及评价，查阅有关“物质性质探究能力”的文献，了解物质性质探究能力的发展进阶、对应教学策略及评价内容与方式，构建物质性质探究能力发展框架。结合“物质性质必做实验”的具体内容进行教学规划，确定不同阶段的教学实施内容、学生在不同学习阶段的预期发展目标以及教学策略，进行相关的教学设计并实施。在教学实施后对学生发展情况进行诊断，在实施实验探究诊断时，采取课中表现性评价，课后题目测查、问卷调查、学生访谈等方式综合进行评价，根据学生发展的诊断结果分析，寻找学生物质性质探究能力发展的证据，从而得出结论。研究结果表明：①初中生物质性质探究能力通过不同阶段的学习是得到持续性发展的。首先提出问题的角度以及认识物质的角度得到发展，从性质、用途角度发展成从性质、用途、组成、转化以及类别角度分析，从关注单一物质发展到关注一类物质；性质预测从生活经验抽提信息，到从资料中获取，再到基于相似性，简单概括一类性质进行预测，最后能基于类别，利用一类物质性质，演绎推理预测物质性质；在设计实验方案方面，表达方式多样，逐渐关注实验药品、实验仪器、实验步骤，从基于反应本身选取试剂与实验装置，到基于证据选取试剂与实验装置，设定操作步骤；在实施实验方案时操作逐渐熟练、有条不紊，有目的的寻找化学反应发生的证据；能从单一角度到多角度、从直接到间接获取证据；在分析解释证据时从对单一物质的实验证据进行分析和推理，确立因果关系到归纳、演绎确立一类物质的性质，并自主论证；实验结束后由简单交流自己的实验过程到能够通过交流了解他人的结论和观点，获得更多数据和信息，完善探究的结论，最后能够通过交流探究的过程和方法，评价现有的实验方案，并进行改进。不过对于物质性质探究思路与方法的应用、知识迁移能力以及陌生情境中实验方案的设计意图的论证等发展较慢，需要循序渐进。②初中生在不同阶段的物质性质探究能力的实然发展水平与笔者预期的学生发展目标、不同阶段物质性质探究能力发展指标大致相符合，由此可以说明笔者构建的物质性质探究能力发展框架符合学生发展，提出的对应四个阶段的教学策略以及对应的教学设计是有效的。阶段一的教学策略：通过联系生活中的物质培养学生对于熟悉物质的性质预测的能力；通过实验让学生更加深刻的体会实验是研究物质性质的重要方法；通过小组合作经历完整的探究过程，引导学生在反思和交流的基础上，发展证据意识，提炼研究单一物质性质的一般思路与方法。阶段二的教学策略：通过来自生产、生活中的真实实例，引导学生发现问题、提出问题，发展学生的提问能力；在问题驱动下开展物质性质的探究，通过小组交流讨论设计出实验方案并进行验证，应用并完善单一物质性质探究的思路与方法。阶段三的教学策略：利用身边的金属或金属材料的使用这一真实情境，引导学生关注一类物质的性质。通过实验探究，学生在观察中获得证据，在描述现象的活动中进行归纳，在交流评价中进一步认识金属这一类物质的共性和差异性，结合探究过程概括或提炼出研究金属这一类物质性质探究的基本思路与方法。阶段四的教学策略：通过比较、归纳盐酸和硫酸的性质，建立对酸这类物质的认识，得出酸具有的共性；启发学生从组成上理解不同的酸在化学性质上具有共性的原因，逐步建立研究酸这类物质性质及其变化的基本思路。相同类别的物质具有类似的性质与变化，就具有类似的分析视角和应用价值，由此可以引导学生尝试按这一思路预测其他酸的性质，突出分类法研究物质的价值。在学习氢氧化钠、氢氧化钙这两种碱的性质时，则可让学生采用类比的方法，将研究酸的共性的基本方法迁移到碱的共性的学习中。

Material property is an important content support for students to learn material, understand the world, learn scientific methods, experiment and explore and social practice, and carry out the comprehensive implementation and development of students' core quality. And students must do experiments is the basis and guarantee of students learning chemistry and exploring activities. Taking "chemistry must do experiments" as the carrier to carry out in-depth "investigation of material properties" can not only cultivate students' basic chemical experiment skills, but also help them to learn and form ideas and methods of investigation of material properties, so as to develop their exploration ability.
Under this research background, this study firstly analyzes the content related to the two learning topics of "scientific inquiry and chemical experiment" and "material properties and application" according to the Chemistry Curriculum Standards for Compulsory Education (2022 Edition). Then, literature on "experimental inquiry ability" is consulted to analyze the development, teaching strategy and evaluation of experimental inquiry ability. Refer to the literature on "material property inquiry ability", understand the development of material property inquiry ability, corresponding teaching strategies and evaluation contents and methods, and
construct the development framework of material property inquiry ability. Combined with the specific content of "experiments must be done with material properties", the teaching implementation content of different stages, students' expected development goals and teaching strategies in different learning stages were determined, and related teaching design and implementation were carried out. After the implementation of teaching, the development of students is diagnosed. During the implementation of experimental investigation and diagnosis, performance evaluation in class, after-class question test, questionnaire survey, student interview  and other methods are adopted for comprehensive evaluation. Based on the analysis of the diagnosis results of students' development, evidence of the development of students' ability to explore material properties is found, so as to draw a conclusion.
The results show that: (1) Junior high school students' ability to explore material properties has sustained development through different stages of learning. Firstly, the perspective of raising
questions and understanding substances has been developed, from the perspective of nature and use to the perspective of nature, use, composition, transformation and category analysis, from the focus on a single substance to a class of substances. The property prediction is based on extracting information from life experience, obtaining information from data, and then simply summarizing a kind of property based on similarity. Finally, the property of a kind of material can be predicted by deductive reasoning based on class. In terms of the design of experimental scheme, there are various ways of expression, gradually paying attention to experimental drugs, experimental instruments and experimental steps, from the selection of reagents and experimental devices based on the reaction itself to the selection of reagents and experimental devices based on evidence, and the setting of operating procedures; In the implementation of the experimental scheme, the operation becomes more and more proficient and orderly, and the evidence of chemical reaction is looked for purposefully. Able to obtain evidence from a single
Angle to multiple angles, from direct to indirect; In the analysis and interpretation of evidence, from the analysis and reasoning of the experimental evidence of a single substance, to establish causality, induction, deduction to establish the conclusion of a class of substances, and independent demonstration; After the experiment, I can simply communicate my own experimental process to understand others' conclusions and views through communication, obtain more data and information, and improve the conclusion of exploration. Finally, I can evaluate and improve the existing experimental scheme through the communication of
exploration process and methods. However, the application of ideas and methods for exploring material properties, the ability of knowledge transfer, and the design intention of experimental schemes in unfamiliar situations develop slowly, which requires gradual progress.(2) The actual development level of junior high school students' ability to explore material properties at different stages is roughly in line with the author's expected development goals and development indicators of the ability to explore material properties at different stages, which indicates that the framework of the development of the ability to explore material properties constructed by the author is in line with the development of students, and the proposed teaching strategies
corresponding to the four stages and corresponding teaching design are effective. The teaching strategy of Stage 1: cultivate students' ability to predict the nature of familiar materials by
associating them with the material in life; Experiment is an important way to study the properties of matter. Through group cooperation, students are guided to develop their awareness of evidence on the basis of reflection and communication, and to refine general ideas and methods for studying specific material properties. Teaching strategy of stage 2: Guide students to find and raise questions through real examples from production and life, and develop students' questioning ability; Carry out the exploration of material properties driven by problems, design and verify the experimental scheme through group communication and discussion, and apply and improve the thought and method of exploring the properties of a single substance. Teaching strategy of Stage 3: Guide students to pay attention to the nature of a kind of substance by using the real situation of the use of metal or metal materials around them. Through exploration, students can obtain evidence through observation. Summarize in the activities of describing phenomena, further understand the commonness and difference of metals in the communication and evaluation, and summarize or refine the basic thoughts and methods of studying the properties of metals in combination with the exploration process. The teaching strategy of stage 4: By comparing and summarizing the properties of hydrochloric acid and sulfuric acid, the understanding of acid is established and the common characteristics of acid are obtained.
Enlighten students to understand the reason why different acids have common chemical properties from composition, and gradually establish the basic idea of studying the properties and changes of acids. Substances of the same category have similar properties and changes, so they have similar analytical perspectives and application value. Therefore, students can be guided to try to predict the properties of other acids according to this idea, highlighting the value of studying substances by classification method. In the study of the properties of sodium hydroxide and calcium hydroxide, students can use analogy to transfer the basic method of studying the generality of acids to the study of the generality of bases.