Exothermic is reaction that release heat from the system to surrounding. For this reaction, the reactants have higher enthalpy compared to the products. The enthalpy change will always negative. Figure 1 shows the energy profile diagram for exothermic reaction.
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| figure 1 |
Endothermic reaction is reaction that absorbs heat from the surrounding to the system. The reactants have lower enthalpy compared to the products and the enthalpy change will always positive. Figure 2 shows the energy profile diagram for endothermic reaction.
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| figure 2 |
