FINIAL Flashcards
true or false: Solubility is an important technique in organic synthesis because it is one of the steps in isolating the product you made.
true
Which chemical solvent used in this solubility experiment should you have the most respect when handling?
Methylene chloride
What is the definition of miscibility?
One liquid mixes with another to form an homogeneous solution.
What is the most important reason in organic chemistry to perform a recrystallization?
To purify a solid
If you were recrystallizing sulfanilamide today which solvent would you use?
ethanol
What is the first step in the recrystallization technique?
choose the appropriate solvent for that particular solid.
What is the final step in the recrystallization process?
Wash the crystals with cold solvent.
If you were working in the lab today, which compound would you be recrystallizing in the recrystallizing lab?
Sulfanilamide
At what rate should your temperature change to obtain the best results for a melting point technique?
2 degrees per minute
True or false: The melting point technique will give you an exact melting point, not a melting point range.
false
True or false: After loading your sample in the capillary tube, you should drop it several time through a glass tube to compact the sample.
true
True or false: To determine the identity of your unknown sample, you should mix it with a compound whose melting point is known.
true
True or false: Determining the melting point is a good indicator of a sample’s purity.
true
true or false: Multiple extractions result in less product isolation (less efficiency) than one extraction.
false
What is the purpose of using MgSO4 in the extraction experiment?
It is a drying agent to remove water from the propanoic acid.
What is the dangerous concern when working with diethyl ether?
It is explosive and flammable.
true or false: Extraction is the process of selectively removing a compound of interest from a mixture using a solvent. Washing is the process of selectively removing unwanted compounds from a mixture using a solvent.
true
In the extraction experiment what layer will your final product, propanoic acid, be in?
Organic layer
true or false: most of the compounds you would use in the distillation lab are flammable compounds
true
What is the proper drip rate to ensure a good distillation?
one-to-two drops per second
How will you know when the first of your two compounds has distilled over to the receiving flask?
When the drop rate and temperature start to decrease.
true or false: You should always distill your still pot (round bottom flask) to dryness
false
Which type of distillation requires more glassware?
fractional
What does Rf stand for?
Retention factor
