HomeworkLib
Question

Why must the spot applied to a TLC plate be above the level of the developing...

Why must the spot applied to a TLC plate be above the level of the developing solvent? What problem will ensue if the level of the developing liquid is higher than the applied spot in a TLC analysis?

science   chemistry   
0 0
Add a comment Improve this question Transcribed image text
Next > < Previous
Sort answers by oldest

Homework Answers

Answer #1

0 0
Add a comment
Know the answer?
Add Answer to:
Why must the spot applied to a TLC plate be above the level of the developing...
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for? Ask your own homework help question. Our experts will answer your question WITHIN MINUTES for Free.
Similar Homework Help Questions

  • Determine the Rf value of the substances A, B, and C on the TLC shown. Show...

    Determine the Rf value of the substances A, B, and C on the TLC shown. Show your calculation! What will happen if the applied spot is lower than the level of the developing liquid? What will be the result of applying too much compound on a TLC plate? What is the reason that the mobile phase travels up the silica gel plate (TLC plate)? 4. Determine the Rf value of the substances A, B, and Con the TLC shown. Show...

  • 1. Why should any marks on the TLC y marks on the TLC plate be done...

    1. Why should any marks on the TLC y marks on the TLC plate be done in pencil and not pen? 2. A spot on a TLC plat migrates 4.2 cm as the solvent plates my migrates 4.2 cm as the solvent plates migrates 8.0 cm up the plate. What is the Rivalue for this spot? Show your calculati

  • 1) A student develops their TLC plate and places it under a UV light, but nothing...

    1) A student develops their TLC plate and places it under a UV light, but nothing appears. What mistake might the student have made? a) Spotted the compound below the level of eluent b) Spotted the compound above the level of eluent c) Used a sample that was too concentrated d) Used too much sample 2)Thin layer chromatography, TLC, is commonly used to monitor reactions to completion. Using this technique, what would indicate to a student that the reaction is...

  • Why is it important to spot the TLC plate quickly and lightly?

    Why is it important to spot the TLC plate quickly and lightly?

  • 1. A solution of the sample to be analyzed has been made in a suitable solvent...

    1. A solution of the sample to be analyzed has been made in a suitable solvent and wil l be provided for you. With this solution, a small spot is applied at a distance hear the bottom of the edge of a TLC plate using an applicator. (see Figure 1) This spot must be above the level of solvent in the TLC chamber. Why? 2. The plate is placed in a developing chamber containing the appropriate solvent (eluent), covered, and...

  • 3. TLC analysis of an unknown sample using pure ethyl acetate as a developing solvent gives a single spot with an Rf va...

    3. TLC analysis of an unknown sample using pure ethyl acetate as a developing solvent gives a single spot with an Rf value of 0.08 1 points A. Explain why this result does not guarantee that the sample is a pure compound. B. Suggest two changes that could be made to the experiment to improve the analysis of the unknown sample. 2 points Change 1 Change 2

  • Below is a picture of a TLC plate by a student using this technique and developing...

    Below is a picture of a TLC plate by a student using this technique and developing a TLC plate for the first time. You can see that the yellow compound from the spot is actually traveling downward and into the solution, as opposed to upward with a capillary action. The reason for this failed attempt is a major error in the performed technique,acommon mistake about which the student was warned multiple times prior to the lab work. What did she...

  • For TLC plate separation, why do we use Rf values instead of distance measurements (e.g. the...

    For TLC plate separation, why do we use Rf values instead of distance measurements (e.g. the spot travelled 5 cm from the starting line)? What would happen if we compared solvent systems using distances rather than Rf values?

  • Referring back to question 5 above, in the TLC plate on the left the eluting mobile...

    Referring back to question 5 above, in the TLC plate on the left the eluting mobile phase solvent was ethyl acetate, in the plate on the right it was 97% ethyl acetate and 3% methanol. Explain why the Rf values in the plate on the right are larger than those in the plate on the left. Your explanation must be in the terms of intermolecular forces, you are not allowed to only use the word "polarity". There are THREE dynamical...

  • 3. If the TLC plate development had stopped before the solvent front reached the top of...

    3. If the TLC plate development had stopped before the solvent front reached the top of the TLC plate (i.e. maybe it reached the middle of the TLC plate when it was stopped, instead): a) Would the Rf values have been affected? If so, how? If not, why not? Give a numerical example to support your answer. b) Would the size of the spots have been affected? If so, how? If not, why not? (Hint: think about the diffusion of...

ADVERTISEMENT
Free Homework Help App
Download From Google Play
Scan Your Homework
to Get Instant Free Answers
Need Online Homework Help?
Ask a Question
Get Answers For Free
Most questions answered within 3 hours.
ADVERTISEMENT
ADVERTISEMENT