Figure 11. Graphical illustration of the measured values by smartphone (SP) (left) and photometer (right) (PH), including the approximations.

From

Catalysis Revisited An Overview of Classical School Experiments and New Approaches for a Better Conceptual Understanding

Marco Reinmold, Julian Grob, Bastian Hohm, Arnim Lühken

World Journal of Chemical Education. 2023, 11(3), 104-113 doi:10.12691/wjce-11-3-14