Exothermic and Endothermic
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Exothermic and Endothermic
To confirm, all change in a reaction that is exothermic is a -negative value and vise versa for endodermic?
Re: Exothermic and Endothermic
Yes, you are correct when the enthalpy of a reaction is overall negative it will be exothermic and if it is overall positive it will be endothermic.
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Re: Exothermic and Endothermic
Yup, exothermic reactions have negative enthalpy, because heat is released from the system in those reactions, while endothermic reactions have positive enthalpy since those reactions absorb heat into the system.
Re: Exothermic and Endothermic
Yes, exothermic reactions have negative delta H and endothermic have positive.
Re: Exothermic and Endothermic
NATALY CORTES 3H wrote:To confirm, all change in a reaction that is exothermic is a -negative value and vise versa for endodermic?
Yes, I think about it by correlating the negative value as giving off heat corresponding to exothermic while endothermic reactions require heat and correspond to a positive value.
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Re: Exothermic and Endothermic
Yes. Exothermic is negative because heat is "lost"/released from the system. Endothermic is positive because heat is needed/added/goes into the system.
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Re: Exothermic and Endothermic
Yes, an exothermic reaction is when the system loses energy and there is therefore a negative enthalpy. Endothermic reactions absorb energy back into the system and therefore there is a positive enthalpy overall for the reaction. Remember that this relates to the heat of the reaction and you sometimes have to include work when calculating internal energy.
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Re: Exothermic and Endothermic
Yes! exothermic reactions will be negative because they are losing heat to the system (like when bonds are created), and endothermic reactions are positive because energy is required to make the reaction proceed (like when bonds are broken). Exothermic reactions cause a decrease in temperature in the system, while endothermic reactions involve an increase in temperature.
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Re: Exothermic and Endothermic
Yep! I at first confused the definitions of exothermic and endothermic and thought that temperature increases with exothermic reactions and decreases with endothermic reactions. However, it is the opposite situation. Exothermic reactions result in a temperature decrease because heat is released from the system, whereas endothermic reactions result in a temperature increase because heat is being absorbed by the system. Therefore, since exothermic reactions lose heat they have negative enthalpy (total heat content in a system). Thus, since endothermic reactions absorb heat they have positive enthalpy.
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