Is it possible to have an Rfnumber greater than 1? Why or why not? -In order to have an Rfvalue greater than 1 the pigment would have to move further than the solvent. Since the pigment is carried by the solvent an Rfgreater than one is not possible.
Q. What will be the result of adding too much sample to the TLC plate?
Step 3: Spot the TLC plate If the sample is too concentrated, it will run as a smear or streak (see troubleshooting section below); if it is not concentrated enough, you will see nothing on the plate. Sometimes you will need to use trial and error to get well-sized, easy to read spots.
Table of Contents
- Q. What will be the result of adding too much sample to the TLC plate?
- Q. What does the RF value mean?
- Q. What is the formula for calculating the Rf value of an amino acid?
- Q. What is RF and how does it define protein identification?
- Q. Why do amino acids have different RF values?
- Q. What type of reaction is required to break down a dipeptide into individual amino acids?
- Q. Why do pink and purple amino acids attract each other?
- Q. What is the RF value of aspartame?
- Q. How do you identify an amino acid mixture?
- Q. Why do we cover the beaker with a lid?
- Q. Why do we need to cover the developing chamber using aluminum foil?
- Q. Why do we need to cover the beaker with aluminum foil or Saran Wrap chromatography?
Q. What does the RF value mean?
RF value (in chromatography) The distance travelled by a given component divided by the distance travelled by the solvent front. For a given system at a known temperature, it is a characteristic of the component and can be used to identify components.
Q. What is the formula for calculating the Rf value of an amino acid?
The Rf value can be calculated by measuring the distance of the substance from its starting point in millimeters, as well as the distance the solvent traveled from its starting point in millimeters, then dividing the substance distance by the solvent distance.
Q. What is RF and how does it define protein identification?
The Rf is defined as the migration distance of the protein through the gel divided by the migration distance of the dye front. The distance should be measured from the top of the resolving gel to the band of interest, as illustrated on the gel.
Q. Why do amino acids have different RF values?
The different amino acids move at differing rates on the paper because of differences in their R groups. Rf is simply the distance the biomolecule moved through the filter paper divided by the distance the solvent moved through the paper. See the appendix for more details on how to measure Rf.
Q. What type of reaction is required to break down a dipeptide into individual amino acids?
This animation shows how a peptide bond in the middle of a dipeptide may be broken (hydrolysed). This takes place as a result of the addition of water. This splits the bond, supplying -H to one end and -OH to the other.
Q. Why do pink and purple amino acids attract each other?
Why do purple and pink amino acids attract each other? The positive and negative charged amino acids attract each other to create a neutral charge. All the hydrophobic amino acids (nonpolar) are clustered together.
Q. What is the RF value of aspartame?
0.4
Q. How do you identify an amino acid mixture?
Detection of amino acids can be achieved readily by the “ninhydrin color test”, whereby an alcoholic solution of the triketone, “ninhydrin”, is heated with an amino acid and produces an intense blue-violet color.
Q. Why do we cover the beaker with a lid?
The reason for covering the container is to make sure that the atmosphere in the beaker is saturated with solvent vapour. Saturating the atmosphere in the beaker with vapour stops the solvent from evaporating as it rises up the paper.
Q. Why do we need to cover the developing chamber using aluminum foil?
A- It is important to keep the developing chamber covered with plastic wrap during the development of the chromatogram so the solvent vapor can saturate the air in the chamber, the solvent does not evaporate and the chromatogram develops properly and shows the correct cations present.
Q. Why do we need to cover the beaker with aluminum foil or Saran Wrap chromatography?
The reason for covering the beaker is to make sure that the atmosphere in the beaker is saturated with solvent vapor. To help this, the beaker is often lined with some filter paper soaked in solvent. Saturating the atmosphere in the beaker with vapor stops the solvent from evaporating as it rises up the plate.
