Question

would you expect the viscosity of 1-pentanol to be larger or smaller than the viscosity of 1-butanol?

would you expect the viscosity of t-butanol (CH3)3COH to be larger or smaller than the viscosity of 1-butanol?

Answer 1

Viscostiy increases with increasing hydrocarbon chain due to increase in van der Waals forces as area of contact between molecules increases.

Therefore we expect 1-pentanol will have higher viscosity than 1-butanol as 1-pentanol has larger hydrocarbon chain associated with it.

Viscosity of t-butanol (CH3)3COH, will be smaller than 1-butanol as t-butanol has less surface area, therefore for less van der Waals forces.

Area of contact between the molecules of t-butanol will be less due to its compact structure, therefore less van der Waals forces.