thin layer chromatography
DESCRIPTION
Thin Layer Chromatography. This animation is about thin layer chromatography and how it can be used to separate components from a mixture. - Dhrubajyoti Samanta. Master Layout. 1. 2. 3. 4. 5. Definitions and animation directions:. 1. - PowerPoint PPT PresentationTRANSCRIPT
Thin Layer Chromatography
- Dhrubajyoti Samanta
This animation is about thin layer chromatography and how it can be used to separate components from a
mixture.
24/01/11
Master Layout
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24/01/11
Definitions and animation directions:
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1• The silica gel is a white solid which does not move during the course of the animation.• The solvent, and the dots representing the components/ compounds move upwards during the course of the reaction.• The polarity levels determine the heights to which the components/compounds rises.•The solvent front rises to a constant height in each of the cases (say 4 inches).•The distance moved by the component/compound dots depend on the polarity of the solvent. The distance moved by the components is given by the table in the slides following each situation.
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Thin Layer Chromatography (TLC)
Animation Area
- Dhrubajyoti Samanta
Please move the slider to choose the polarity of the components/compounds and the polarity of the solvent. Then press the start button to initiate the process of chromatography.
Interactivity Options Area :Choice Based
Step 1: 1
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Display the text in the blue box Display the text in the blue box one sentence at a time
*Read the sentences in the box as they appear*
Thin Layer Chromatography is a technique by which components of a mixture may be separated based on differences in their polarity using an adsorbing agent (eg. Silica) which is taken in the form of a thin layer.The separation of the components depends on several factors, namely: the differences in polarity of the components and the polarity of the solvent depending on the type of adsorbing agent used.Taking silica as the adsorbing agent, a larger difference in polarity of the components causes an increase in the separation of the components and a greater polarity of the solvent leads to a decrease in the separation after a certain point.A characteristic of a component is given by the RF Value which is given by the equation :
Another use of thin layer chromatography is to compare two substances. This is often used to determine the extent to which a reaction has taken place.
Step 2: 1
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Inputs are asked
The previous data is slowly erased from the screen and the above figure is shown. The animation waits for the user to hit one of the two buttons in the red squares
Please click on either of the two options.
Step 3 – option compare: 1
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Chromatography with Fixed polarity of compounds and solvent
The above shown diagram is displayed and the user is asked to press the start button to start the animation. No choices are shown.
Here are two compounds in a moderately low polar solvent mixture. The orange compound is non polar and the yellow compound is highly polar. Please press the start button to start the chromatography process.
Step 4 – option compare: 1
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Chromatographic Movement
The solvent slowly moves from the initial blue line to the final blue line. The dots also slowly move from the initial dot to the final dot. The distance each dot or liquid line moves depends on the polarity chosen as described in the description.
The compounds move to their equilibrium positions whose height depends on the polarities of the components. The highly polar compound stays low while the non polar compound moves to a higher level.
Step 5 – option compare: 1
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Action Description of Action Audio Narration
Rf values are shown
The Rf value for each compound is calculated according to the distances moved by the dot of that compound and the liquid column. These values are then displayed on the screen.
The Rf values of the two compounds are :Compound 1: …(*calculated*)Compound 2: …(*calculated*)
Step 6 – option compare: 1
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Chromatography with Fixed polarity of compounds and variable solvent
The above shown diagram is displayed and the user is asked to press the start button to start the animation after entering the polarity of the solvent in the slider as shown in the next slide.
Here are the same two compounds but now you may change the polarity of the solvent. 0 is non polar and 10 is highly polar. Please move the slider to choose your input and then press the start button to start the chromatography process.
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Input Directions
Step 7 – option compare: 1
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Chromatographic Movement
The solvent slowly moves from the initial blue line to the final blue line. The dots also slowly move from the initial dot to the final dot. The distance each dot or liquid line moves depends on the polarity chosen as described in the next slide.
The compounds move to their equilibrium positions whose height depends on the polarities of the components. The highly polar compound stays low while the non polar compound moves to a higher level.
Output DirectionsThe distances moved by the compounds follow the following curves.
Step 8 – option compare: 1
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Action Description of Action Audio Narration
Rf values are shown
The Rf value for each compound is calculated according to the distances moved by the dot of that compound and the liquid column. These values are then displayed on the screen.
The Rf values of the two compounds are :Compound 1: …(*calculated*)Compound 2: …(*calculated*)
Step 9 – option compare: 1
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Chromatography with Fixed polarity of solvent and variable compounds
The above shown diagram is displayed and the user is asked to press the start button to start the animation after entering the polarities of the compounds in the sliders as shown in the next slide.
Here are two compounds again, but this time the polarity of the solvent is fixed at a low value of polarity and you will be able to change the polarity of the compounds. Please do so and press the start button.
Input directions
Step 10 – option compare: 1
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Chromatographic Movement
The solvent slowly moves from the initial blue line to the final blue line. The dots also slowly move from the initial dot to the final dot. The distance each dot or liquid line moves depends on the polarity chosen as described in the next slide.
The compounds move to their equilibrium positions whose height depends on the polarities of the components. The highly polar compound stays low while the non polar compound moves to a higher level.
Output DirectionsThe dots move to height according to the polarity as shown in the following graph.
Step 11 – option compare: 1
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Action Description of Action Audio Narration
Rf values are shown
The Rf value for each compound is calculated according to the distances moved by the dot of that compound and the liquid column. These values are then displayed on the screen.
The Rf values of the two compounds are :Compound 1: …(*calculated*)Compound 2: …(*calculated*)
Step 3 – option separate: 1
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Chromatography with Fixed polarity of components and solvent
The above shown diagram is displayed and the user is asked to press the start button to start the animation. No choices are shown.
Here is a two component mixture in a moderately low polar solvent mixture. The red component is non polar and the yellow component is highly polar. Please press the start button to start the chromatography process.
Step 4 – option separate : 1
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Chromatographic Movement
The solvent slowly moves from the initial blue line to the final blue line. The dots also slowly move from the initial dot to the final dot. The distance each dot or liquid line moves depends on the polarity chosen as described in the description.
The components move to their equilibrium positions whose height depends on the polarities of the components. The highly polar component stays low while the non polar component moves to a higher level.
Step 5 – option separate : 1
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Action Description of Action Audio Narration
Rf values are shown
The Rf value for each component is calculated according to the distances moved by the dot of that component and the liquid column. These values are then displayed on the screen.
The Rf values of the two components are :Component 1: …(*calculated*)Component 2: …(*calculated*)
Step 6 – option separate : 1
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4Action Description of Action Audio Narration
Chromatography with Fixed polarity of components and variable solvent
The above shown diagram is displayed and the user is asked to press the start button to start the animation after entering the polarity of the solvent in the slider as shown in the next slide.
Here is the same two component mixture but now you may change the polarity of the solvent. 0 is non polar and 10 is highly polar. Please move the slider to choose your input and then press the start button to start the chromatography process.
24/01/11
Input Directions
Step 7 – option separate : 1
5
3
2
4Action Description of Action Audio Narration
Chromatographic Movement
The solvent slowly moves from the initial blue line to the final blue line. The dots also slowly move from the initial dot to the final dot. The distance each dot or liquid line moves depends on the polarity chosen as described in the next slide.
The components move to their equilibrium positions whose height depends on the polarities of the components. The highly polar component stays low while the non polar component moves to a higher level.
Output DirectionsThe distances moved by the components follow the following curves.
Step 8 – option separate : 1
5
3
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Action Description of Action Audio Narration
Rf values are shown
The Rf value for each component is calculated according to the distances moved by the dot of that component and the liquid column. These values are then displayed on the screen.
The Rf values of the two components are :Component 1: …(*calculated*)Component 2: …(*calculated*)
Step 9 – option separate : 1
5
3
2
4Action Description of Action Audio Narration
Chromatography with Fixed polarity of solvent and variable components
The above shown diagram is displayed and the user is asked to press the start button to start the animation after entering the polarities of the components in the sliders as shown in the next slide.
Here is the two component mixture again, but this time the polarity of the solvent is fixed at a low value of polarity and you will be able to change the polarity of the components. Please do so and press the start button.
Input directions
Step 10 – option separate : 1
5
3
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4Action Description of Action Audio Narration
Chromatographic Movement
The solvent slowly moves from the initial blue line to the final blue line. The dots also slowly move from the initial dot to the final dot. The distance each dot or liquid line moves depends on the polarity of the components chosen as described in the next slide.
The components move to their equilibrium positions whose height depends on the polarities of the components. The highly polar component stays low while the non polar component moves to a higher level.
Output DirectionsThe dots move to height according to the polarity as shown in the following graph.
Step 11 – option separate : 1
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Action Description of Action Audio Narration
Rf values are shown
The Rf value for each component is calculated according to the distances moved by the dot of that component and the liquid column. These values are then displayed on the screen.
The Rf values of the two components are :Component 1: …(*calculated*)Component 2: …(*calculated*)
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Links for further readingBooks: Vogel’s Textbook of Practical Organic Chemistry, 5th Edition, A.I. Vogel, A.R. Tatchell, B.S. Furnis, A.J. Hannaford, P.W.G. Smith, Prentice Hall, 1996.
Internet Reference: http://courses.chem.psu.edu/chem36/Experiments/PDF%27s_for_techniques/TLC.pdf