Lab Report Guidelines and Organic Molecules Lab

Lab Report Components

  • Results: Can be presented as a picture or typed out. Ensure the presentation is clear and organized.
  • Discussion Questions: Include answers to the discussion questions in the lab manual.
  • Conclusion: A brief summary of the lab's purpose and the findings.

Lab Report Guidelines

  • The lab report should focus on the current organic molecules lab, not the properties of water lab from the previous week.
  • Clearly label each section: Introduction, Materials and Methods, Results, Discussion, Conclusion.
  • The lab report should be approximately four pages, including the title page.

Lab Report Format

  • Introduction: Two paragraphs covering background information and the purpose of the lab.
  • Materials and Methods: Around five sentences, using bullet points to list the materials used.
  • Results: Include graphs and data obtained during the experiment.
  • Discussion: Answers to the discussion questions provided.
  • Conclusion: A concise summary of the experiment and its findings.

Identification of Organic Molecules Lab

  • The lab involves using unknown substances labeled x, y, and z to test for the presence of different organic molecules.
  • Use various indicators to test for sugar, starch, protein, and lipids.

Experimental Procedures

  • Benedict's Test:
    • Tests for the presence of sugar.
    • Add Benedict's solution (the indicator for sugar) to the substance.
    • Heat the mixture on a hot plate for a few minutes.
    • A color change indicates a positive result for sugar.
    • If the color change barely occurs compare to just the substance and indicator to eliminate false positives due to hidden sugar.
  • Iodine Test:
    • Tests for the presence of starch.
    • Add a couple of drops of iodine to the substance.
    • A blue-black color indicates a positive result for starch.
  • Biuret Reagent Test:
    • Tests for the presence of proteins.
    • A violet color change indicates a positive result for proteins.
    • A cobalt blue color may appear. Compare the substance with the indicator alone to check for a color difference.
  • Sudan IV Test:
    • Tests for the presence of lipids.
    • Place drops of substances x, y, and z on brown paper bags and allow them to dry.
    • Check for greasy spots on the other side of the bag, which indicates the presence of lipids.
    • Reference a video for expected results, as this test may not always give clear indications.
  • Sucrose Inversion Test:
    • Uses Benedict’s solution again after an inversion process

Team Work

  • Divide the tasks among group members to efficiently conduct all tests.
    • One person can do the Benedict's test and the sucrose inversion test.
    • Another can do the iodine test.
    • Someone else can perform the Biuret test.
    • Share the data.