Now that you have finished the viscosity measurements, follow the prompts in your lab manual to analyze the data. Investigating the results from the viscosity experiment can provide information about the composition of the biodiesel and glycerol produced in your synthesis reaction, as well as provide insights into how your biodiesel might perform in an engine.
Start by reviewing the times you recorded. Those times correspond to how long it took for each sample to travel a specific distance under the influence of gravity. How can you use these times to rank the viscosity of the different samples? How do these times correspond to viscosity?
Compare your results for the different biodiesel samples (commercial vs student-made). Do these results tell you anything about the composition of the biodiesel you synthesized? How well was the biodiesel purified? Similarly, compare the results between the pure glycerol and the glycerol from the synthesis. What do the results tell you about their compositions?
Lastly, think about using biodiesel vs unreacted vegetable oil. Can you explain why a conventional diesel engine would be able to use biodiesel without any modification, whereas vegetable oil can only be used if the engine is adapted properly?