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sqa higher chemistry help!!

i know im cutting it close cause the exam is tomorrow but i was doing the 2012 higher chemistry past paper and im stuck on question 26 in paper 1

it shows a reaction and its enthalpy change and asks what the energy released would be if two moles of the reactants are mixed and ignited

the reactants have a 5 to 4 more ratio between them

if anyone could help asap id appreciate it!!
You multiply the enthalpy by 2/5, because if u do u have 1.6 moles of the 4 mole one and 2 moles, I don't know how to explain it properly, but you can use jabchem as they have solutions made
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Original post by marchofthepigs
i know im cutting it close cause the exam is tomorrow but i was doing the 2012 higher chemistry past paper and im stuck on question 26 in paper 1
it shows a reaction and its enthalpy change and asks what the energy released would be if two moles of the reactants are mixed and ignited
the reactants have a 5 to 4 more ratio between them
if anyone could help asap id appreciate it!!

in this case N2O4 is the limiting reactant here, so if there is 2 moles of each reactant is used. 2/5 x the enthalpy change shold give you the correct answer.

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