Lab D- Tlc

Front 1

Chromatography Definition

Back 1

Technique used to separate organic compounds by using a solvent (mobile phase) to move the compounds over a solid (stationary phase)

Front 2

Compound Separation

Back 2

Depends on how strongly they bind to the stationary phase via non-covalent interactions vs. how well they dissolve in the mobile phase

Front 3

Uses of TLC

Back 3

Determine how many components are in a mixture

Determine purity or identity of a compound

Front 4

Silica Gel

Back 4

Form of SiO2, polar substance that can hydrogen bond to organic molecules

Solvent is called eluent

Front 5

Effect of Polarity on TLC

Back 5

Less polar compounds will move farther up the plate than more polar ones

Front 6

Three Compounds

Back 6

9-hydroxyfluorene (most polar)

Phenyl benzoate

fluorene (least polar)

Front 7

Rf

Back 7

Ratio of the distance traveled by a given compound to the distance traveled by the solvent

Always between 0 and 1, no units

Less polar = higher Rf value

Front 8

General Rule for eluent

Back 8

A more polar solvent will move a compound further up the TLC plate and vice versa

Front 9

Benzene Ring Feature

Back 9

Absorbs UV light, shows up as a pink spot under UV lamp

Front 10

Procedure

Back 10

1. Prepare solvent beaker (9mL hexane + 1mL ethyl acetate)

2. Let sit while covered

3. Prepare plate and spot it

4. Run plate while covered

5. Remove, draw line and circles

6. Calculate Rf values

Front 11

Waste Disposal

Back 11

TLC solvent mixture: TLC solven waste

TLC Capillaries: sharps container

TLC plates: biohazard waste boxes

Front 12

Types Chromatography

Back 12

TLC

LC (Liquid Chromatography/Column Chromatography)

HPLC (High Performance LC. Uses pressure to force mp through small column)

GC (Gas Chromatography)

Front 13

TLC Make up

Back 13

Thin Layer: 250 μm of silica gel (SiO2)8

Front 14

Common Developing Solvents

Back 14

(listed by increasing polarity)

alkanes/cycloalkanes, Toluene, DCM, Diethyl Ether, Ethyl Acetate, Acetone, Alcohols, Acetic Acid, Water

Front 15

TLC Set Up

Back 15

Front 16

Fluorene

Back 16

Front 17

9-hydrofluorene

Back 17

Front 18

Phenyl Benzoate

Back 18

Front 19

Apply Small spots

Back 19

Avoid tailing

Front 20

Polarities Organic Compounds

Back 20

Alkanes < Alkenes < Aromatic Hydrocarbons < Ethers/Halocarbons < Aldehydes/Ketones/Esters < Alcohols < Amines < Carboxylic Acids < Salts

Front 21

Common Developing Solvents

Back 21

Alkanes/Cycloalkanes < Toluene < DCM < Diethyl Ether < Ethyl Acetate < Acetone < Alcohols < Acetic Acid < Water