Chapter 5: Lab Techniques Flashcards
How would you allow for the extraction of an amine to occur?
Through the use of diluted strong acid (HCl) and separate the aqueous layer from the organic one.
How would you allow for the extraction of a carboxylic acid to occur?
The use of 5-10% NaHCO3 to create an aqueous layer to be separated.
What would you use to separate a phenol?
Not sodium carbonate since it is too weak, I would use a strong base.
Explain Thin Layer chromatography
The use of a silica gel and treat it with non-polar solvent to allow development. Then place sample onto the gel.
Column Flash chromatography
uses the same method of silica polar gel but with bulkier compounds. The NP substance will elute first followed by the polar substance
Ion Exchange Chromatography
Method to separate proteins at various pI and pH levels. A portion of the protein (+) will attach to the anion column and slow elution. Will then move out due to a concentrated cation solution.
HPLCC
High-performance liquid chromatography allows for a pressurized chromatography procedure. Polar will elute after non-polar substance
Reverse HPLCC
Polar will elute first instead of a Non-polar substance.
Size Exclusion Chromatography
The beads will have pores to allow for the movement of small molecules to elute after the larger ones.
Affinity Chromatography
Used to purify proteins, nucleic acids by the use of antibody binding and centrifugation.
What are three physical features that alter the melting and boiling points of compounds?
Molecular weight, Branching, and the ability to hydrogen bond with compounds.
When do you use simple distillation set up? Fractional?
Use a simple method when the boiling points are very different from each other while fractional when the boiling points are closer to each other.
Explain Mass Spec
Pretty much the tallest peak is what the mW of the compound is, however other peaks exist due to isotopes present of the compound.
What is the Bromine Rule?
2 peaks of equal ratio at 79 and 81 mw
What is the chlorine rule?
2 peaks ( a 1/3 of the height from each other) at the mw of 35 and 37
