Endothermic v. Exothermic
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Re: Endothermic v. Exothermic
Endothermic and exothermic reactions are always positive and negative delta Hs, respectively. That is because endo/exothermic reactions are basically defined using this metric
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Re: Endothermic v. Exothermic
Yes, I believe that positive delta H values always indicate endothermic reactions, while negative delta H values always indicate exothermic reactions.
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Re: Endothermic v. Exothermic
Yes, exothermic reactions will have a negative delta H, indicating the release of heat while endothermic reactions will have a positive delta H, indicating the absorption of heat. It's important to keep in mind that gibs free energy depends on both the delta H, delta S, and temperature so the delta H of a reaction does not tell us anything about its delta G.
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Re: Endothermic v. Exothermic
ΔH<0, exothermic, releases heat;
ΔH>0, endothermic, absorbs heat;
ΔG<0, exergonic, spontaneous;
ΔG>0, endergonic, not spontaneous.
ΔH>0, endothermic, absorbs heat;
ΔG<0, exergonic, spontaneous;
ΔG>0, endergonic, not spontaneous.
Re: Endothermic v. Exothermic
Positive delta H represents endothermic while negative delta H represents exothermic.
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Re: Endothermic v. Exothermic
Yes an endothermic reaction always has a positive delta H value and exothermic reaction always has a negative delta H value.
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Re: Endothermic v. Exothermic
Yes, it is true. Exothermic reactions will always have a negative delta H and endothermic reactions will always have a positive delta H. This is how you can distinguish between the two!
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Re: Endothermic v. Exothermic
I think that's the right way to think about it! Delta H being positive or negative is the main constant indicator of a reaction being endothermic or exothermic
Re: Endothermic v. Exothermic
Yes, for endothermic reactions delta H will always be positive because heat will be absorbed and for exothermic reactions delta H will always be negative because heat will be lost.
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Re: Endothermic v. Exothermic
Generally, endothermic reactions will have a positive delta H whereas exothermic reactions will have a negative delta H.
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Re: Endothermic v. Exothermic
Yes, endothermic reactions will always have a positive delta H while exothermic reactions have a negative delta H. There won't be exceptions to this rule, because delta H is meant to directly indicate when a reaction is exo-/endothermic.
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Re: Endothermic v. Exothermic
So, for a process carried out at constant pressure, if the heat added to the system is positive (endothermic), ΔH is positive and if the heat added to the system is negative (exothermic, heat removed from system), ΔH is negative.
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Re: Endothermic v. Exothermic
So, for a process carried out at constant pressure, if the heat added to the system is positive (endothermic), ΔH is positive and if the heat added to the system is negative (exothermic, heat removed from system), ΔH is negative.
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Re: Endothermic v. Exothermic
correct! Endothermic reactions will always have a positive delta H, and exothermic reactions will always have a negative delta H.
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Re: Endothermic v. Exothermic
So, for a process carried out at constant pressure, if the heat added to the system is positive (endothermic), ΔH is positive and if the heat added to the system is negative (exothermic, heat removed from system), ΔH is negative.
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Re: Endothermic v. Exothermic
Hello. An endothermic reaction will always have a positive delta H because heat is required. If you have a negative delta H then you know that heat is being released and you have an exothermic reaction. These values are set in stone and never change conceptually. Hope this helps.
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Re: Endothermic v. Exothermic
Endothermic reactions will always have a positive delta H since heat is required. Exothermic reactions will always have a negative delta H and you know that heat is being released and you have an exothermic reaction.
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Re: Endothermic v. Exothermic
Hi!
Yes! Endothermic will have a positive enthalpy, and exothermic will have a negative enthalpy.
Yes! Endothermic will have a positive enthalpy, and exothermic will have a negative enthalpy.
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Re: Endothermic v. Exothermic
Hi, yes endothermic reactions will always have a positive delta H and exothermic reactions will have a negative delta H. This is because heat is required and heat is released, respectively.
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Re: Endothermic v. Exothermic
Hi! Yes, exothermic reactions will always have a negative ΔH value because overall, the reaction releases heat (enthalpy of reactants is greater than enthalpy of products), so the enthalpy change is negative (ΔH = H products - H reactants). Meanwhile, endothermic reactions will always have a positive ΔH value because overall, the reaction takes up heat (enthalpy of products is greater than enthalpy of reactants), so the enthalpy change is positive.
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Re: Endothermic v. Exothermic
By definition, endothermic reactions will have a positive delta H because products have to have more energy than reactants to be classified as endothermic. The opposite is true for exothermic (negative delta H, reactants have more energy than products).
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Re: Endothermic v. Exothermic
Yes, the definition of endothermic and exothermic are related to their delta H values, so you will not find exceptions. Endothermic will always have a positive delta H and exothermic will always have a negative delta H.
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Re: Endothermic v. Exothermic
Hi, ΔH for an exothermic reaction will always be negative since energy is released. ∆H for an endothermic reaction will always be positive since energy is absorbed. Hope this helps!
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Re: Endothermic v. Exothermic
Yes this is true because a negative delta H would indicate a release of energy (exothermic) whereas a positive delta H would indicate taking in energy or an endothermic reaction.
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Re: Endothermic v. Exothermic
Yes. If a system is absorbing heat (endothermic), delta H will be positive. If a system is releasing heat (exothermic), delta H will be negative.
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Re: Endothermic v. Exothermic
As far as I know, if you have a delta H that is positive then you have an endothermic reaction. If the delta H is negative then you have an exothermic reaction.
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Re: Endothermic v. Exothermic
Yes, exothermic means that the change in enthalpy is negative and endothermic means that the change in enthalpy is positive.
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Re: Endothermic v. Exothermic
yes, they will always have a positive delta H because they are endothermic reactions. likewise, the opposite direction of the phase changes will be exothermic and have a negative delta H, such as going from gas to liquid (condensation) and going from liquid to solid (freezing).
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Re: Endothermic v. Exothermic
Yes, endothermic reactions will always have a positive delta H value because heat is required and exothermic reactions will have negative delta H values because heat is released from the system.
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Re: Endothermic v. Exothermic
Yes, endothermic reactions will always have a positive delta h and the exothermic reactions will have a negative delta h. To my understanding, delta h represents the internal change of energy in a system (going in or out). So, you can remember this by thinking the negative value is energy leaving the system, and positive value represents energy going into the system.
Re: Endothermic v. Exothermic
yes, exothermic will always be negative because they are releasing heat and endothermic will always be positive because it needs heat
Re: Endothermic v. Exothermic
I'm pretty sure that endo is always (-) and exo is always (+). However, I dont know if its possible to have 0 dH value.
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Re: Endothermic v. Exothermic
Yes, endothermic reactions will always have a positive delta H and exothermic rxns have negative delta H.
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Re: Endothermic v. Exothermic
Yes, exothermic reactions always have a negative change in H because H of reactants is higher than that of the products and endothermic reactions have a positive change in H because H of the reactants is lower than that of the products.
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Re: Endothermic v. Exothermic
Exothermic means the reaction is giving off heat so delta h is negative and endothermic means the reaction requires heat so delta h is positive
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Re: Endothermic v. Exothermic
Yes endothermic has a positive delta H and exothermic has a negative delta H.
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Re: Endothermic v. Exothermic
Yes, endothermic reactions always have positive delta H, while exothermic reactions always have a negative delta H.
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Re: Endothermic v. Exothermic
Yes, exothermic reactions will always have a negative delta H value while endothermic reactions will always have a positive delta H value
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Re: Endothermic v. Exothermic
Endothermic reactions require heat, and enthalpy is in regards to the system, so a positive enthalpy value means that the system gains energy (heat).
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