VISCOSITIES OF N-ALKYL CHLORIDES FROM 15-DEGREES-C TO 80-DEGREES-C

The viscosities of n-alkyl chlorides from pentyl to hexadecyl chloride were determined at temperatures between 15 to 80 degrees C at 5 degre es C intervals. The intrinsic volumes of the n-alkyl chlorides were de termined by extrapolation of the plot of fluidity against molar volume to zero fluidity. Plots of the logarithm of viscosity vs, reciprocal absolute temperature were almost linear. The energies of activation fo r viscous flow for the n-alkyl chlorides were calculated and found to increase with increase in chain length. The fluidities, phi, of the n- alkyl chlorides were found to obey the modified form of Hildebrand's e quation, phi = D[(V - V-o)/V-o] exp(-E-B/RT) where D is a constant, V and V-o are the molar volume and the intrinsic molar volume, respectiv ely, and E-B is an energy term corresponding to the energy required fo r disrupting the association of the molecules. The activation energy f or viscous flow consists of the sum of the energy required for the exp ansion of the void volume and the energy required to overcome intermol ecular interactions. These energies were calculated and discussed.