Answer:
The fraction of (a) ethylene to (b) propylene repeat units is 163 to 100
Explanation:
Suppose that we get 100 g of the given co-polymer sample, in that sample it consists of 52 g of (a) and 48 g of (b), the MW of (a) is 28 and (b) is 42.
Then we calculate the mole of each polymer in the sample
n (a) = 52/28 = 1.86
n (b) = 48/42 = 1.14
Hence, the fraction of (a) to (b) is n(a)/n(b) = 1.86/1.14 = 163/100
