Endo vs Exo thermic
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Endo vs Exo thermic
If we are given a question about equilibrium changes in response to heat, are we only expected to know whether a reaction is exothermic or endothermic based on the sign of the delta H value?
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Re: Endo vs Exo thermic
If the delta H value is positive, it is an indication that the reaction is endothermic. If it is a negative value then it is exothermic because a negative delta H means energy was lost because it was released when products were formed.
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Re: Endo vs Exo thermic
You are going to be given the delta H value, which allows you to determine if the reaction is exothermic or endothermic. To find whether it favors the products or reactants, you can treat heat to be either a reactant or product depending on the type of reaction and see how it changes due to temp increase or decrease.
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Re: Endo vs Exo thermic
For changes in enthalpy, you can refer to the ∆H value to determine whether or not the reaction is endothermic or exothermic. If the ∆H value is positive, it means that the equation requires heat in order to move forward; therefore the reaction is endothermic. If the ∆H value is negative, it means that the reaction releases heat and is therefore exothermic.
For endothermic reactions, an increase in temperature will cause an increase in K. However, the reaction quotient (Q) is not affected by temperature since there is no change in concentration. As a result, Q < K because K increases, and the net reaction moves toward the products. The same is true, just in reverse, for exothermic reactions.
For endothermic reactions, an increase in temperature will cause an increase in K. However, the reaction quotient (Q) is not affected by temperature since there is no change in concentration. As a result, Q < K because K increases, and the net reaction moves toward the products. The same is true, just in reverse, for exothermic reactions.
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Re: Endo vs Exo thermic
Yes, the question should give the delta H value. I think the change in enthalpy can also be understood through thermochemistry and bond energies but we don’t need to know this yet.
Re: Endo vs Exo thermic
Given the delta H, we can say the reaction is endothermic if delta H is positive and that the reaction that a negative delta H means the reaction is exothermic. For now, that seems to be what we need to know.
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Re: Endo vs Exo thermic
Yes, if the delta H value is positive, the reaction is endothermic as it requires heat. If the delta H value is negative, the reaction is exothermic which means it releases heat.
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Re: Endo vs Exo thermic
If ∆H is negative, that means the reaction is exothermic. This is because a negative enthalpy implies giving off heat from the system to the surroundings. Similarly, a positive ∆H value would mean the reaction is endothermic, heat is added to the system from the surroundings for the reaction to take place.
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Re: Endo vs Exo thermic
If you are given delta H, you should be able to figure out whether a reaction is exothermic or endothermic. If the delta H is positive, it is endothermic and if it is negative it is exothermic.
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Re: Endo vs Exo thermic
Like most of my peers stated, positive delta H value=endothermic and negative delta H value is negative= exothermic.
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Re: Endo vs Exo thermic
If delta H is positive the reaction is endothermic. If delta H is negative it is exothermic
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Re: Endo vs Exo thermic
Hello. So we know that when you have a gain in energy and a positive delta H value your equation is going to be considered endothermic. When you have a loss of energy and a negative delta H value your equation is going to be exothermic. Exothermic is associated with the release of heat while endothermic is associated with required heat. Hope this helps.
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Re: Endo vs Exo thermic
Hello,
If the delta H is positive, that means that the reaction is endothermic (requires energy as a reactant)
If the delta H value is negative, that means that the reaction is exothermic (releases energy)
If the delta H is positive, that means that the reaction is endothermic (requires energy as a reactant)
If the delta H value is negative, that means that the reaction is exothermic (releases energy)
Re: Endo vs Exo thermic
I would assume so, if delta H is positive it is endothermic and if it is negative it is exothermic.
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Re: Endo vs Exo thermic
If the delta H value is negative, then the reaction is exothermic, as it releases energy. If the delta H is positive, then the reaction is endothermic, and it absorbs energy.
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Re: Endo vs Exo thermic
Given the delta H value we are expected to know whether the system is endothermic or exothermic. If delta H > 0 (positive) it will be endothermic (take in heat) while if delta H < 0 (negative) it will be exothermic (release heat). With this information we can determine whether the reaction is going towards products or reactants depending on if we are increasing or decreasing the temperature.
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Re: Endo vs Exo thermic
If the change in enthalpy is positive, that mean it is endothermic and if the enthalpy is negative, that means the reaction is exothermic
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Re: Endo vs Exo thermic
If the problem does not tell you if its endothermic or exothermic, you would most likely be given a delta H, or enthalpy value. If this is negative, then it is releasing heat and is therefore exothermic. If it is positive, then it is absorbing heat and is therefore endothermic. Hope this helps!
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Re: Endo vs Exo thermic
If delta H is positive, then the reaction is endothermic. If delta H is negative, then the reaction is exothermic.
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Re: Endo vs Exo thermic
Yes, we will only be expected to know whether a reaction is endo or exothermic based on the delta H value. In other questions we may be asked about shifting left or right, but that has to do with how K responds to changes in temperature which is a different type of question.
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Re: Endo vs Exo thermic
Yes, I believe so. If ΔH is positive, the reaction is endothermic. If ΔH is negative, the reaction is exothermic.
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Re: Endo vs Exo thermic
Yes, if given the delta H value, you can determine whether the reaction is exothermic or endothermic. If the delta H value is positive, then the reaction is endothermic because heat is required in the reaction. If the delta H is negative, then the reaction is exothermic because heat is given off to the surroundings.
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Re: Endo vs Exo thermic
Yes if delta H is given we know that the reaction is exothermic if it is negative and endothermic if it is positive.
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Re: Endo vs Exo thermic
I don't know if we will need to calculate for delta H, but if we are given its value we can easily figure out if the reaction is endothermic or exothermic. If delta H is negative the reaction is exothermic as heat is given off to its surroundings. If the delta H is positive, then the reaction is endothermic as heat is required for it to occur.
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Re: Endo vs Exo thermic
Yes, we would be expected to know if a reaction is endo or exothermic when given the H value. We can determine this by remembering that if delta H is negative the reaction is exothermic, and if delta H is positive, the reaction is endothermic.
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Re: Endo vs Exo thermic
Yeah you can tell if a reaction is endo or exothermic because a -△H indicates a exothermic reaction, or one that releases energy, while a +△H value indicates an endothermic reaction or one that requires energy.
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Re: Endo vs Exo thermic
Exothermic reactions have a negative delta H and endothermic reactions have a positive delta H. This is because endothermic reactions take in heat while exothermic reactions give off heat.
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Re: Endo vs Exo thermic
Yeah I think so. Either they'll give you change in H (or they'll give you parts of it to calculate change in H of the overall reaction) or they'll say it explicitly
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Re: Endo vs Exo thermic
If they are asking whether the reaction is exo or endothermic and they provide the ∆H value then you can determine what the reaction is. If ∆H is negative, this means that the reaction is releasing energy as it proceeds and is EXOthermic. If ∆H is positive, this means that the reaction requires energy to proceed and is ENDOthermic.
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Re: Endo vs Exo thermic
A positive delta H would indicate that the reaction is endothermic while a negative delta H would indicate an exothermic reaction.
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Re: Endo vs Exo thermic
Hello!
Yes, you can determine whether a reaction is endothermic or exothermic by looking at the sign of the delta H value. If the delta H value is negative the reaction is exothermic. If the delta H value is positive the reaction is endothermic. Hope this helped!
Yes, you can determine whether a reaction is endothermic or exothermic by looking at the sign of the delta H value. If the delta H value is negative the reaction is exothermic. If the delta H value is positive the reaction is endothermic. Hope this helped!
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Re: Endo vs Exo thermic
The deltaH value is a very efficient way to determine whether a reaction is exothermic or endothermic. If it is negative, the reaction is exothermic. In contrast to a positive value signifying an endothermic reaction.
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