Density and Viscosity of 1-Alkanols

Densities and viscosities have been measured for twelve 1-alkanols from methanol to 1-dodecanol at temperatures ranging from 303.15 to 323.15 K. Molar volumes, V m , have been calculated from the density data, which have been found to follow the additive equation, V m = V CH3 + nV CH2 + V OH, where n is the number of CH2 groups. V m have been plotted against n, showing an excellent linear relationship. The average values of V CH2 at 303.15 K and 323.15 K have been determined from the slopes of this equation. The viscosities have been found to increase almost exponentially with the number of carbon atoms at different temperatures. The thermodynamic activation parameters, free energy, ▵G ≠, enthalpy, ▵H ≠, and entropy, ▵S ≠ for viscous flow have been plotted against the number of C atoms – all have been found to increase with the chain length of 1-alkanols.