Thermochemical Equation Determine Mass

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To solve the problem of calculating the mass of copper produced when 1.47 x 10^4 kJ is consumed in the reaction 2Cu2O(s) → 4Cu(s) + O2 with ΔH = +333.8 kJ/mol, it's crucial to understand that the ΔH value refers to the enthalpy change for the entire reaction, not just for one mole of copper. The correct approach involves recognizing that the reaction produces 4 moles of copper for every 333.8 kJ consumed. Therefore, to find the number of moles of copper produced, divide the total energy consumed by the enthalpy change per reaction and then multiply by the stoichiometric ratio of copper produced. This leads to the correct calculation, resulting in 11.2 kg of copper produced, clarifying the misunderstanding regarding the initial calculation.
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So I am doing practice problems from the textbook and it states:

Given the thermochemical equation: 2Cu2O(s) → 4Cu(s) + O2, ΔH =+333.8 kJ/mol, calculate the mass of copper produced when 1.47 x 104 kJ is consumed in this reaction

My attempt

(1.47 x 104 kJ)/(33.8 kJ/mol )= 44 mol x 2 2 60=5.284 kg
BUT This is wrong and I don't know why...the answer is 11.2 kg
 
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No idea what you did, what is "2 2 60"?

It is 333.8 kJ per "mole of reaction", not "mole of copper".
 
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