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**Daniel123****Member**- Registered: 2007-05-23
- Posts: 663

Hello everyone

Exams nearly over now! Woo!

I had my chemistry today, and there was a 1 mark question that asked for the empirical formula of poly(e)thene. I wasn't sure, but I thought that the empirical formula was the basic, canceled down formula - so wouldn't the formula for polythene be the same as the formula for ethene C2H4, as polythene is a chain of 'n' ethene molecules?

I can't seem to find the answer on the internet. Perhaps someone could enlighten me?

Thanks

P.S This is my 100th post :D:D:D

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**mathsyperson****Moderator**- Registered: 2005-06-22
- Posts: 4,900

You're right in that the empirical formula is the cancelled down formula (so a ratio of amounts rather than actual amounts), but unfortunately that means that the answer should be CH2. Very bad luck, you did the hardest bit and then fell down because of a small oversight.

Still, it happens to everyone. I'm sure you did well in the rest of it.

Why did the vector cross the road?

It wanted to be normal.

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**Daniel123****Member**- Registered: 2007-05-23
- Posts: 663

OHHHHHHH that is so annoying!!!

I also got the formula for oxygen turning into ozone wrong, so I think I will get around 84 out of 90... which will do.

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