The expectations should be determined when the TLC plate is allowed to remain the chamber of development for long time, so that the solvent reaches at the top of the plate during analysis of mixture. Concept introduction: TLC works on the principle of separation of constituents of a mixture of compounds based on polarity. The polar compounds interact with the stationary phase thus can move to smaller distance from the base. While the non polar compounds tend to move faster as they interact less with the silica gel; therefore, they move far from the base of the plate.

Question

Explain why TLC cannot be used for some volatile low molecular weight substances such as toluene.

Answer 1

Question

Chapter 8, Problem 5Q

Interpretation Introduction

Interpretation:

The expectations should be determined when the TLC plate is allowed to remain the chamber of development for long time, so that the solvent reaches at the top of the plate during analysis of mixture.

Concept introduction:

TLC works on the principle of separation of constituents of a mixture of compounds based on polarity. The polar compounds interact with the stationary phase thus can move to smaller distance from the base. While the non polar compounds tend to move faster as they interact less with the silica gel; therefore, they move far from the base of the plate.

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Explain why TLC cannot be used for some volatile low molecular weight substances such as toluene.

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