Lab # 10
11/26
Sample # 32 for TLC
Sample # 1 for Paper
Introduction: Chromatography is one of the most important separation techniques used in all fields of chemistry ranging from analytical chemists to pharmacists. The understanding of how chromatography works and how to operate instruments used to carry out the procedures is an important lab technique to learn.
Experiment: Thin Layer Chromatography. Lab #10-1 Paper Chromatography. Lab #10-2
Theory:
Ethyl Acetate-Solvent used in TLC (mobile phase).
Dichloromethane- Solvent used to dissolve all samples used to compare unknown in TLC
Silica Gel Plates- TLC plates. Stationary phase
Elemental Iodine- used to accentuate the spots on the TLC plates so we can measure Rf.
Asprin(Acetylsalicylic acid)- First compound used on TLC plate to compare the unknown.
Salicylamide(o-hydroxybenzamide)-Second compound used on TLC plate to compare unknown.
Caffine(1,3,7-Trimethylxanthine)-Third compound used on TLC plates to compare unknown.
Acetone- Solvent A used in paper chromatography.
Ethanol- Solvent B used in paper chromatography.
Dithiooxazmide- Spray used to show to spots on paper chromatography
Sodium Diethyldithiocarbamate- Second spray used to show spots on paper chromatography
Ammonia- Fumes were used to bring about the spots on the filter paper in paper chromatography.
Results:
Unknown in TLC was Aspirin
Unknown in Paper was Nickel
Rf Asprin-5.5cm/7= .78
Rf Salicylamide-6.3cm/7= .9
Rf Caffine-1.2cm/6.3= .19
Rf Unknown(TLC)-5.5cm/7=.78
Rf Cobalt solvent #1-5.1/6.5=.78
Rf Copper solvent #1-5.7/6.5=.87
Rf Iron solvent #1=1
Rf Nickel solvent #1-1.4/6.7=.21
Rf Unknown(Paper) solvent #1-1.3/6.5=.21
Rf Cobalt solvent #2=.88
Rf Copper solvent #2=.86
Rf Iron solvent #2=.91
Rf Nickel solvent #2=.94
Rf Unknown(Paper) solvent #2=.91
Calculations:
Rf Unknown(Paper) solvent #1-1.3/6.5=.2
Discussion: In