Consider a sample of polyethylene containing 2000 chains with molecular weights ranging from 0 to 4000 g/mol; 4000 chains with molecular weights ranging from 4000 to 8000 g/mol; 3000 chains with molecular weights ranging from 8000 to 12000 g/mol; and 1500 chains with molecular weights ranging from 12000 to 16000 g/mol. Calculate the following: a. the weight average molecular weight.
b. the number average molecular weight
c. the polydispersity
d. the degree of polymerization