The student clearly stated the independent variable, juice content, and the dependent variable, total reducing capacity, in the research question, establishing a clear relationship. The methodology was well-defined, including the use of KMnO₄ titration and the rationale for selecting juice brands for comparison. The student identified controlled variables and discussed safety considerations related to the chemicals used. However, the student did not adequately address the ethical and environmental issues associated with the investigation and needed to clarify the absence of ethical concerns and provide a disposal plan for potassium permanganate. Overall, the methodology was sufficiently detailed and free from irrelevant information, allowing for reproducibility.
