How does heat affect TLC visualization with sulfuric acid?

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Heating can significantly affect TLC visualization, particularly when sulfuric acid is involved. Elevated temperatures can lead to the evaporation of solvents, potentially causing spots to disappear or become messier due to increased molecular motion. Sulfuric acid catalyzes the charring of organic compounds at around 120°C, enhancing visualization. The discussion emphasizes the importance of temperature control during TLC analysis. Understanding these effects is crucial for accurate interpretation of results.
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Homework Statement



How does heating affect the spots on the TLC?

Homework Equations



None

The Attempt at a Solution



I have no clue, unless heating evaporates the solution and therefore the spots disappear?
or Perhaps the elutent evaporated due to heat rather then the solution?
 
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Heating may or maynot affect the components of the organic solvents which have been adsorbed in the adsorbent.

however, if the temp is high enough, then the solvent may vaporize.
 
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oahbpn said:

Homework Statement



How does heating affect the spots on the TLC?

Homework Equations



None

The Attempt at a Solution



I have no clue, unless heating evaporates the solution and therefore the spots disappear?
or Perhaps the elutent evaporated due to heat rather then the solution?

The higher temperature may (just a guess) make the sample spot become messier because of the increased random motion of the molecules of solvent. If this is correct, then maybe someone can transcribe into more precise language.
 
oahbpn said:

Homework Statement



How does heating affect the spots on the TLC?

Homework Equations



None

The Attempt at a Solution



I have no clue, unless heating evaporates the solution and therefore the spots disappear?
or Perhaps the elutent evaporated due to heat rather then the solution?

Is this question being asked in context with another question? Heating a TLC is performed sometimes after treatment with H2SO4. Did you treat the TLC with H2SO4?
 
yes you are correct , chemisttree

sorry about that
 
It's called visulization by charring. The sulfuric acid will catalyze the charring of organic compounds at elevated temperatures (~120C).
 
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