Three mixtures were prepared with very narrow molar mass distribution polyisoprene samples with molar masses of 8000, 25,000, and 100,000 as indicated below.

(a) Equal numbers of molecules

(b) Equal masses of sample

(c) Equal viscosities of sample dissolved in tetra hydro furan

(K = 19.5 L g-1, a = 0.73)

For each of the samples, calculate the number-average and weight-average molar mass, and comment on the meaning of the values obtained.