This laboratory experiment guides students in exploring the concepts of adsorption and absorption 90 through image brightness analysis. Students investigate these phenomena using photographic images of standard CuSO₄ solutions and the particle size of dried fish scales. They create a calibration curve using a smartphone-based colorimetry method and learn to measure the size of the fish scales in cm², using a ruler as a reference in an image with ImageJ. They then measure the color intensity of a CuSO₄ solution of unknown concentration and calculate the percentage of Cu²⁺ ion removal. In the final stage, 95 students test their hypotheses using the Mann-Whitney U Test with Jamovi software. After completing all activities, students should be able to: (i) collect observational data in a table using Google Sheets or Excel, (ii) create a trendline graph to find the R² value, (iii) perform particle size calculations from images using ImageJ, (iv) utilize a smartphone colorimetric method as an alternative to measure the unknown concentration of a CuSO₄ solution using a calibration curve, (v) identify the differences between 100 adsorption and absorption phenomena, (vi) evaluate the methods and quality of experimental data, and (vii) suggest improvements to the experiments.