Determination of chemical composition in Tri-Metal Alloys: a three variable linear equation system approach

Abstract

To enhance the bridge between macroscopic and symbolic representations in chemistry, we crafted a laboratory module focusing on a three-equation system for chemical composition analysis. Students assess the composition of copper, tin, and aluminum alloys by measuring two properties: density and heat capacity. These non-destructive procedures fit within standard laboratory session durations. After gathering data, students tackle three linear equations linking element mass ratio to alloy composition, density, and heat capacity. By pooling data from various samples, the class achieves a comprehensive understanding. This method aligns with objectives for laboratory education, emphasizing scientific reasoning, practical skills, and subject mastery. Students’ results deviated by +/-10% from actual alloy compositions. The discussion of student-gathered data and results supports the feasibility of the laboratory experience for its implementation in introductory chemistry laboratories.