Competition with Solvent

Problems Preparation Competition with solvents, substrates Competition with ionic substrates, salts Size of substrate, diffusion... 

Most likely, this competition between solvent and the other organic molecules is responsible for the decrease in the initial selectivity for 2-AMN and in deacylation with the increase of solvent polarity there is a decrease in the residence time of 1-AMN molecules within the zeolite pores with consequently less secondary reactions. However at long reaction times, the highest yield in 2-AMN is obtained with nitrobenzene, a solvent of intermediate polarity, and not with the less polar solvents. It is probably because competition with solvent plays a role in both the residence times of 1-AMN and 2-AMN.25... 

Applicability, versatility broad restricted (competition with solvents, substrates) restricted (competition with ionic substrates, salts) restricted (size of substrate)... 

Possible competition with solvents, substrates Restricted applicability... 

Recently, it has been proved in some applications that large volume injection of samples in hydrophobic solvents (w-hexane, n-pentane, /-octane) is possible, with a gradual reduction of retention and a relatively small loss in terms of peak efficiency. Two conditions are, however, necessary to apply such an injection approach the solutes must be soluble in hydrophobic solvents and, meanwhile, they have to be less hydrophobic than the sample solvent to avoid competition with solvent molecules in partitioning between the mobile phase and the stationary phase. 

The transition of an ion from solution to the gas phase represents a quite drastic change of the environment. In solution, the intermolecular interactions between molecules compete with interactions between these molecules and the solvent, while Ihe ions are isolated in the gas phase and no competition with solvent molecnles exists anymore. 

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