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Calculate the change in enthalpy (LaTeX: \DeltaΔH) of a reaction with the following information:

Energy of Reactants = 129 kJ

Energy of the Products = 110 kJ

Energy of the Transition State = 198 kJ

1 Answer

3 votes

Answer: -19 kJ

Step-by-step explanation:

The change in enthalpy
\Delta H is mathematically expressed as the difference between the the total potential energy of products
U_(products) and the potential energy of the reactants
U_(reactants):


\Delta H=U_(products)-U_(reactants)

Where:


U_(products)=110 kJ=110 (10)^(3)J


U_(reactants)=129 kJ=129 (10)^(3)J

Then:


\Delta H=110 kJ-129 kJ


\Delta H=-19 kJ The negative sign in this result means we have a negative enthalpy, hence an exothermic reaction (where heat is released).

User Vmorusu
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