Upon completing a synthesis, you attempt to purify your material via recrystallization. You dissolve the material in a minimal amount of hot solvent and then immediately place the vessel in an ice bath. You obtain the solid product through vacuum filtration. Any issues here? No issues, this is what you would do! O You may have an impure solid due to rapid cooling of the vessel. O You should have started with RT solvent to dissolve the material. O You should use gravity filtration for the fınal isolation.

REACTION RECRYSTALLIZATION (OPTIONAL) 1. Begin assembling your reflux apparatus (i.e. lab jack, stir plate, exten- sion clamp and round-bottom flask of appropriate size). 10. Weigh your crude solid to calculate an approximate crude yield. Transfer most of it to a 125 mL erlenmeyer, but keep some aside (~100 mg) for analysis at the end. 2. Add para-aminophenol (15.0 mmol), demineralized water ([para- aminophenol] = 0.75 M) and a stirbar to the flask. Set to stir vigorously. 11. Recrystallize your solid by boiling in an erlenmeyer in a minimal volume of demineralized water (~8 mL/gram of crude solid) on a hot plate to fully dissolve it. If necessary, slowly add water portion-wise until a homogeneous solution is obtained. 3. Measure the required volume of acetic anhydride (1.30 eq.) in a small graduated cylinder. Using a platic pipette, add it to the reaction flask. 4. Finish the assembly of the reflux apparatus (i.e. secured water con- denser along with tubing, heating mantle and…

Extraction of Caffeine Post-lab 1. What group of organic compounds does caffeine belong to? 2. Draw the structure of caffeine as a line formula. Redraw the structure of caffeine,showing all carbon and hydrogen atoms. 3. What is the molecular formula for caffeine? Use the molecular formula of caffeine tocalculate its molecular weight. 4. What does it mean for two solvents to be immiscible? 5. On the report sheet, you calculated your percent recovery of caffeine. a. If your percent was less than 90%, give at least one reason why it was less. b. A group of students have their percent yield more than 100%, give at least one reasonwhy it was more than 100%. Do NOT simply say “human error.” Be specific about the typesof errors (human or otherwise) that may have occurred, leading to a recovery more than eorequal to 100% (Is this possible Why?)   6. Based on what you observed during this experiment, is dichloromethane denser OR lessdense than water? Explain your reasoning. 7. Based on what…

For the boxes on top of the arrow, fill in the reagent(s) and solvent(s). Tf- 1. HQ. 2.