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Topic: Question about calculating the molecular weight  (Read 276 times)

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Offline tekki

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Question about calculating the molecular weight
« on: November 22, 2020, 09:07:08 PM »
Hi! Today I was doing my homework and I stuck on one exercise. I have to calculate the molecular weight of polypropylene, where n=320. Can someone help me and show me how can I calculate it? Here's the picture to this exercise.



I hope that someone can show me it! It'd mean the world to me!


EDIT: this is my attempt:

mC=12
mH=1
n=320

12*3+1*6=42u

42*320=13440

Answer: the molecular weight of polypropylene equals 13440
« Last Edit: November 22, 2020, 09:32:50 PM by tekki »

Offline Babcock_Hall

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Re: Question about calculating the molecular weight
« Reply #1 on: November 22, 2020, 09:26:01 PM »
It is a Forum Rule (see red link above) that you must show your attempt at answering a problem before we can help you.

Offline tekki

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Re: Question about calculating the molecular weight
« Reply #2 on: November 22, 2020, 09:30:16 PM »
oh, okay, so gimme a few second and I will post this here!

Offline tekki

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Re: Question about calculating the molecular weight
« Reply #3 on: November 22, 2020, 09:33:19 PM »
It is a Forum Rule (see red link above) that you must show your attempt at answering a problem before we can help you.


I updated my post :)

Offline Borek

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Re: Question about calculating the molecular weight
« Reply #4 on: November 23, 2020, 03:34:46 AM »
Very close, but technically incorrect.

What about the ends?
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Offline tekki

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Re: Question about calculating the molecular weight
« Reply #5 on: November 23, 2020, 03:36:22 AM »
Is it gon' be 13440u? Or you meant something else?

Offline Borek

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Re: Question about calculating the molecular weight
« Reply #6 on: November 23, 2020, 05:47:20 AM »
Polymer chain doesn't start nor end with a sticking out unused bond.
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