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QJEEM19Ch6894: JEE Main 2019 Chemistry - Class 12 JEEM19Ch6894 Solution: In chromatography, which of the following statements is…
In chromatography, which of the following statements is incorrect for Rf ?
Multiple Choice Options
- A Rf value depends on the type of chromatography.
- B Higher Rf value means higher adsorption.
- C Rf value is dependent on the mobile phase.
- D The value of Rf can not be more than one.
Step-by-Step Verified Solution
Rf =
= Distance moved by the substance from baseline
= Distance moved by the solvent from baseline
Option A : Correct. The Rf value can depend on the type of chromatography being used because different methods can use different stationary and mobile phases, which can influence how far a substance travels.
Option B : Incorrect. The Rf value is actually inversely related to adsorption. A higher Rf value indicates that the substance is less strongly adsorbed to the stationary phase, and therefore moves further along with the mobile phase.
Option C : Correct. The nature of the mobile phase can greatly influence the Rf value. The more compatible the substance is with the mobile phase, the further it will travel, leading to a higher Rf value.
Option D : Correct. By definition, the Rf value cannot exceed one, as a substance cannot travel further than the solvent.
So, Option B is incorrect for the Rf value in chromatography.
= Distance moved by the substance from baseline
= Distance moved by the solvent from baseline
Option A : Correct. The Rf value can depend on the type of chromatography being used because different methods can use different stationary and mobile phases, which can influence how far a substance travels.
Option B : Incorrect. The Rf value is actually inversely related to adsorption. A higher Rf value indicates that the substance is less strongly adsorbed to the stationary phase, and therefore moves further along with the mobile phase.
Option C : Correct. The nature of the mobile phase can greatly influence the Rf value. The more compatible the substance is with the mobile phase, the further it will travel, leading to a higher Rf value.
Option D : Correct. By definition, the Rf value cannot exceed one, as a substance cannot travel further than the solvent.
So, Option B is incorrect for the Rf value in chromatography.