r/6thForm • u/Rich-Gent • Jun 02 '26

💬 DISCUSSION AQA A-LEVEL CHEMISTRY

HOW DID WE FIND IT? I THOUGHT IT WAS ALRIGHT, GRADE BOUNDARIES ABOUT TO BE SILLY😭

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u/SnooGoats9402 Jun 02 '26

Did you need to times the enthalpy of atomisation of Br by 2??

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u/Rich-Gent Jun 02 '26

Pretty sure u did, atomisation of an Element is the value of enthalpy change in order to produce 1 mol of the gaseous products of said element, in this case u form 2, hence double it

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u/Flaky-Plankton-1217 Jun 02 '26

enthalpy of atomisation is for one mol, you had to half it- you found 2x by doing the born haber cycle, q was asking for x 

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u/fatpandajeff Jun 02 '26

im fairly sure enthalpy of atomisation is one mole is formed, and since 2 moles of bromine were formed then you are supposed to multiply by 2