Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

You are an engineer working for a company that synthesized and uses polymers for

ID: 985909 • Letter: Y

Question

You are an engineer working for a company that synthesized and uses polymers for a range of products. A competitor makes an identical polymer, PET, but its properties are superior. One of the organic chemistries in your company comes up to you one day and says he has reproduced the competitor’s product exactly because it has the same number average molecular weight. Your response is:

He must be demented because he is wearing an UNC Chapel Hill basketball tee shirt. He is also an organic chemist and cannot possibly be right.

He is right, even if he is demented. An average is an average and the samples must be equivalent.

He is wrong because the distribution of molecular weights could be very different.

He is right because if the distributions are different then the average would also be different. Also, he would only be truly demented if he was wearing a Duke tee shirt.

Explanation / Answer

The number average molecular weight is the total weight of the sample divided by the number of molecules in the sample.

He is wrong because the distribution of molecular weights could be very different.

Because maybe he has the same number average molecular weight but the molecules and distribution are not the same. Or may have more molecules as more molecular weight.

Hire Me For All Your Tutoring Needs
Integrity-first tutoring: clear explanations, guidance, and feedback.
Drop an Email at
drjack9650@gmail.com
Chat Now And Get Quote