Instructions for Recrystallization lab report:
• You must have an introduction stating the purpose of the
experiment. Cite any sources used even if it is the handout provided
for the experiment. Do not plagiarize but summarize in your own
words.
• You must identify the best solvent for recrystallization to purify the
unknown. Remember to look at all different conditions on how to
choose the best solvent to purify the compound.
• You must list the steps/procedures on how you would recrystallize the
unknown if you were to tell someone to do such in the lab. Imagine
you are the professor, and I am the student (role reversal). You can
use the videos provided as guidance. List your own experimental
procedures as steps 1, 2, 3, etc.
• Once you have written down the steps on how to recrystallize the
unknown, you must use the melting point of pure product to identify it
based on the table of reagents provided.
• You must calculate percent recovery based on the original amount of
sample.
• Sources of errors to look for: inaccurate melting point, low percent
recovery. You must also explain why the sources of errors and how
you would correct such errors.
• Submit your final report as a PDF file only. NO other formats will be
graded.
Data:
Unknown #43
Physical appearance: heterogenous mixture of white powder with SiO2
(sand, insoluble impurities)
Mass of unknown before recrystallization: 2.45 g
Mass of unknown after recrystallization: 2.00 g
Melting point of recrystallized unknown: 101.0 – 102.5 CelsiusSolubility of Unknown #43 in different solvents
Solvent Cold
temperature
Room
Temperature
Boiling
Temperature of
solvent
Acetone Soluble Soluble soluble
Water Insoluble Soluble soluble
Toluene Insoluble Insoluble soluble
Hexane Insoluble Insoluble soluble