Calculations on Chemical kinetics activation energy energy profile

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Calculations on Chemical kinetics activation energy energy profile

ISIFE EDUBLOG · ⏱ 3:35 · 55 مشاهدة · 5 years ago

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so if you look at this question we want to solve one problem on the energy profile consider the energy profile below that is this profile here the reactants started from here and the product is formed at this point so the question is that we should determine the activation energy of the reaction and they get the enthalpy change to solve this question activation energy simply means the height of the energy profile so solution to the question activation energy it is the height of the energy profile we have this as the apex here the reaction started from energy 20 and the reaction is completed when the energy is 50. so the energy the activation energy for the reaction will be equal to 50 minus 20 so that is 30 joule that is how to determine activation energy that's from where the reaction started the reactant onto the place you have the core so the distance from here to here is the activation energy for that reaction then the ii question say the enthalpy change enthalpy change of this reaction which is delta is heat of product minus heat of reactant the product in this case now is here then the reactant the heat of the reactant is 20 why the heat of the product is 10 the heat of the product is 30 why the heat of the reactant is 20 so the difference between them will be 10 delta is heat of product minus heat of lambda since the heat of the product is 30 and the heat of the reactants is 20 so the enthalpy change will be 10 joule and it's going to be plus since it is plus now this reaction is an endothermic reaction so whenever question comes under the energy profile that is how to answer the question whether it is exothermic or endothermic when you are looking for the activation energy is just the height of the energy profile you are starting from the right and not the product you are starting from the reactor until where you have the curve the distance there is the activation image then the enthalpy change is the distance between the product and the reactant which you must say the heat of the product minus the heat of the reactants when the heat of product is greater than the heat of the reactant you get positive number just like we have here 13 is greater than 20 that's what we have plus 10 and in that case the reaction is endothermic but in situation where the heat of the product is less than the heat of the reactor you have negative sign and that negative sign shows exothermic reaction because it is taken away from the system thank you so much remember if you have not subscribed before you can hit the subscription button and also the bell there for you to get more videos thank you you