chemistry

posted by .

For a TLC lab,the stationary phase is the mixture of isopropanol and ammonia or the mixture of hexane,ethyl acetate and ethanol, the stationary phase is silica gel. text some dyes and drugs.

which one of the two mobile phases is the more polar? Actualy I need two pieces of evidence... I think the polar one should be the isopropanol and ammonia because it moves slower. Can you help me come up another reason? Thank you~

  • chemistry -

    For a TLC lab,the stationary phase

    I think you mean the mobile phase?

    is the mixture of isopropanol and ammonia or the mixture of hexane,ethyl acetate and ethanol, the stationary phase is silica gel. text some dyes and drugs.

    The isopropanol and ammonia solvent mix is the more polar. Probably the easiest is think which solvent mix is likely to be the more water soluble. Another test is which solvent is most likely to dissolve a polar compound.

    The speed of the solvent front up the TLC plate is governed by a number of things, not least of which is the viscosity of the solvent mixture, and so is not a good key to solvent polarity.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. chemistry

    Once the stationary phase is packed in the column, it is important that the solvent level not drop below the upper level of the stationary phase. Why?
  2. Chemistry

    Liquid Chromatography lab: Why is it important that the solvent level not drop below the upper level of the stationary phase once the stationary phase is packed in the column. is it because if the stationary phase dries out, then the …
  3. Chemistry

    Chromatography How can I tell which of two mobile phases is more polar?
  4. Chemistry

    Chromatography How can I tell which of two mobile phases is more polar?
  5. chemistry

    How can you tell which mobile phase is more polar in TLC?
  6. chemistry

    How can you tell which mobile phase is more polar in TLC?
  7. chemistry

    For a TLC lab,the stationary phase is the mixture of isopropanol and ammonia or the mixture of hexane,ethyl acetate and ethanol, the stationary phase is silica gel. text some dyes and drugs. what is the relationship between the polarity …
  8. Chemistry-help needed

    I have a question on thin layer chromatography (TLC). My mobile phase (i.e. developing solvent) is a mixture of 2 non-polar solvents. After preparing the mobile phase, is it necessary to pour some into the developing chamber to saturate …
  9. Chemistry!!!

    1.)The silica that makes up the stationary phase in TLC chromatophraphy is more polar than the mobile phase. What then might the relative positions of the analgesics on the developed TLC plate tell you about the polarity of these molecules?
  10. Chemistry

    You carry out tlc on silica gel of a mixture of compound A and B. Using a mobile phase of hexane 50% and acetone 50% the Rf values of were A 0.15, B 0.2, and the spots were overlapping. What change would you make to the solvent composition …

More Similar Questions