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# Polypeptide A-level watch

My way is (3*75) + (89*2) + (165*2) = 733. However the correct answer 625, but i don't get why and how. Please someone explain the concept and how to get to the actual answer.
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notice in the equation the H2O molecules are missing - the ones that are supposed to be produced when the polypeptide is made (as it is a condensation reaction)

6 H2O molecules are produced - the Mr of 1 is 18- so 18*6 = 108

733-108=625

welcome, you are
3. (Original post by kolajeex)

notice in the equation the H2O molecules are missing - the ones that are supposed to be produced when the polypeptide is made (as it is a condensation reaction)

6 H2O molecules are produced - the Mr of 1 is 18- so 18*6 = 108

733-108=625

welcome, you are
Wow, in the examiner report they said its a discriminating question and it really is. Thank you so much for helping!
4. (Original post by Revision 99)
Wow, in the examiner report they said its a discriminating question and it really is. Thank you so much for helping!
np, just remember to link everything together and remember the minor details

good luck

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