Abstract: The “Ternary Liquid-Liquid Phase Diagram” is a fundamental experiment in physical chemistry. Mastery of this experiment is essential for students to comprehend the triangular coordinate system and the extraction principle, both of which are widely applied in industrial practices. This paper presents recommendations for improving the content and teaching approach of this experiment, addressing students’ lack of theoretical knowledge and superficial understanding of the experimental process. It proposes integrating a detailed explanation of phase diagram interpretation into the curriculum, emphasizing the relationship between component concentrations and the lengths of parallel line segments on the coordinate axes. This helps students better grasp the movement patterns of system points and the lever rule during the mixing process. Furthermore, the paper clarifies the teaching logic and connections between the ternary phase diagram, the movement of system points on the coordinate axes, and the relationships between component points on tie lines. These suggestions aim to enhance teaching efficiency and facilitate students’ deep understanding of the ternary liquid-liquid phase diagram.

Key words: Physical chemistry experiment, Phase diagram, Ternary liquid-liquid system, Lever rule