7. Energy changes for an endothermic reaction – one where heat is absorbed from the surroundings
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10. Energy changes for an endothermic reaction A—B + C—D Reactants A—C + B—D Products A B C D Bond breaking Bond forming Overall energy change Products have more energy than reactants E
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16. H r Ө depends only on the difference between the standard enthalpy of the reactants and the standard enthalpy of the products, not on the route by which the reaction occurs. This is Hess’s Law – If a reaction can proceed by more than one route the overall enthalpy is the same regardless of which route is followed.
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