The student clearly stated the independent variable as the concentration of hydrogen peroxide and the dependent variable as the time taken for the reaction mixture to turn blue, demonstrating a solid understanding of the research question. However, the student failed to specify the method of analysis for measuring the dependent variable, which should have included details such as the use of a stopwatch and the units of measurement. The methodology was described in sufficient detail, with clear steps and materials listed, ensuring reproducibility. The student identified controlled variables and addressed safety, ethical, and environmental issues associated with the investigation, reflecting a thorough approach to the experiment. Additionally, the student discussed the sampling technique and the choice of trials, contributing to the reliability and clarity of the investigation.
