On the solubility of long n-alkanes in water at room temperature

► MD simulations showed that extended conformations of n-alkanes smaller than n-C22 are preferred in water. ► A geometric description of the different conformations allows the calculation of reliable ΔGc and Ea values in water. ► The solvent-excluded volume increases on passing from a spherical shape to an elongated spherocylindrical one. ► This causes an increase in the magnitude of both ΔGc and Ea, but the latter prevails and chain collapse does not occur.