Because determining average molecular lengths of a sample is difficult, manufacturing companies use ____ for a "quick and dirty" estimation of the average molecular lengths in a sample.
A) polydispersity index
B) melt index values
C) mode values
D) the median value

Question

Because determining average molecular lengths of a sample is difficult, manufacturing companies use ____ for a "quick and dirty" estimation of the average molecular lengths in a sample.  
A) polydispersity index
B) melt index values
C) mode values
D) the median value

Quizplus · Accepted Answer

Melt index values are used by manufacturing companies as a quick and dirty estimation of the average molecular lengths in a sample because they provide an indirect measure of molecular weight, which correlates with molecular length. The melt index measures the flow of a polymer melt under specific conditions, and higher values typically indicate lower molecular weight (and thus shorter molecular lengths).

Because Determining Average Molecular Lengths of a Sample Is Difficult