(a) At the molecular level, what factor is responsible for the steady increase in viscosit...

(a) At the molecular level, what factor is responsible for the steady increase in viscosity with increasing molecular weight in the hydrocarbon series shown in Table?

Table Viscosities of a Series of Hydrocarbons at 20°C

, (b) Although the viscosity varies over a factor of more than two in the series from hexane to nonane, the surface tension at 25 °C increases by only about 20% in the same series. How do you account for this? (c) n-octyl alcohol [CH3(CH2)7OH] has a viscosity of 1.01 × 10-2 kg/m-s, much higher than nonane, which has about the same molecular weight. What accounts for this difference? How does your answer relate to the difference in normal boiling points for these two substances?