Question 26A mixture of leucine and arginine is analyzed by thin layer chromatography with a relatively more polar mobile phase compared to the stationary phase. What is the approximate Rf value of arginine?A.0.30B.0.90C.3D.9
Question
Question 26A mixture of leucine and arginine is analyzed by thin layer chromatography with a relatively more polar mobile phase compared to the stationary phase. What is the approximate Rf value of arginine?A.0.30B.0.90C.3D.9
Solution
The Rf value, or retention factor, is a characteristic of a compound in chromatography. It is defined as the ratio of the distance traveled by the compound to the distance traveled by the solvent.
In thin layer chromatography, compounds are separated based on their polarity. A compound that is more polar will have a stronger interaction with the polar stationary phase and thus move slower, resulting in a lower Rf value. Conversely, a compound that is less polar will have a weaker interaction with the stationary phase and move faster, resulting in a higher Rf value.
In this case, the mobile phase is relatively more polar compared to the stationary phase. This means that the less polar compound (leucine) will move faster and have a higher Rf value, while the more polar compound (arginine) will move slower and have a lower Rf value.
Therefore, the approximate Rf value of arginine would be lower. So, the answer is A. 0.30.
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