Temperature
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Temperature
How would we be asked whether a reaction favors products or reactants based on temperature?
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Re: Temperature
We would need to know if the reaction is endothermic or exothermic and then we could determine which is favors based on the temperature change.
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Re: Temperature
The question would have to say the reaction is endothermic or exothermic, or (what is most probably going to happen) delta H is +, signifying an endothermic reaction, or delta H is negative, signifying an exothermic reaction.
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Re: Temperature
We would need to be given if the reaction is endothermic or exothermic. I assume we will either by told or given delta h.
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Re: Temperature
The question would tell you whether the reaction is exothermic or endothermic. Usually, there is the ∂H which represents the change in enthalpy in the reaction. If the change is positive, that means that there is more "heat" in the products (the right side of the equation), so the reaction is endothermic. Sometimes if the reaction doesn't specify the ∂H of the equation and simply refers to: Reactant(s) + heat <--> Product(s), then this would also be an endothermic reaction as "heat" is necessary for the reaction to proceed. If you were to increase the temperature in the endothermic reaction, then the reaction will shift towards the right (the product side). For exothermic reactions the result is the opposite shifting towards the left, because heat is released as a result of the reaction (reactants <--> products + heat).
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Re: Temperature
Yes, as others stated above, you would need to know whether the reaction is endothermic or exothermic (given by delta h).
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Re: Temperature
Just like everyone else said, the question would have to give you whether or not the reaction is endothermic or exothermic!
If you add head to a reaction that is endothermic (heat is needed for the reaction), the products are favored! I remember it by thinking of heat as a reactant or product, so if it's endothermic, then heat is a reactant. If we add more heat to the reactants, then the products would be favored!
Similarly, if you add heat to a reaction that is exothermic (heat is released in the reaction), the reactants are favored! If you think of it like mentioned before, heat as a product here because it's exothermic, then adding more heat as a product will make the reaction proceed to reactants!
Hope this helps!
If you add head to a reaction that is endothermic (heat is needed for the reaction), the products are favored! I remember it by thinking of heat as a reactant or product, so if it's endothermic, then heat is a reactant. If we add more heat to the reactants, then the products would be favored!
Similarly, if you add heat to a reaction that is exothermic (heat is released in the reaction), the reactants are favored! If you think of it like mentioned before, heat as a product here because it's exothermic, then adding more heat as a product will make the reaction proceed to reactants!
Hope this helps!
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Re: Temperature
We would first have to determine if the reaction given is endothermic or exothermic, which can be seen either through a positive or negative value of Delta H. A positive Delta H would indicate an endothermic reaction, and an increase in temperature for an endothermic reaction will favor products. A negative Delta H would indicate an exothermic reaction, and an increase in temperature for an exothermic reaction will favor reactants.
Re: Temperature
We need to know if the reaction is endothermic or exothermic, which is given by delta h.
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Re: Temperature
Based on if the rxn is endo or exothermic, we can use temperature to find which side the rxn favors
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Re: Temperature
If you know whether the reaction is endothermic or exothermic, you can determine which would be favored.
In an exothermic reaction, if temperature is increased, the reaction shifts left, as heat can be seen as a product of the reaction.
In an endothermic reaction, if temperature is increased, the reaction shifts right
In an exothermic reaction, if temperature is increased, the reaction shifts left, as heat can be seen as a product of the reaction.
In an endothermic reaction, if temperature is increased, the reaction shifts right
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Re: Temperature
We would be asked a question regarding temperature given context on the enthalpy and whether the reaction is endothermic or exothermic.
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Re: Temperature
For endothermic Rxn (delta H is greater than 0, the forward reaction requires energy):
increase temperature--> increases K --> the forward reaction is favored (reaction shifts to the right)
decrease temperature --> decrease K --> reverse reaction is favored
For exothermic reaction (delta H is negative, the reverse reaction is endothermic and requires energy while the forward reaction releases energy):
increase temperature --> reverse reaction is favored --> K decreases
decrease temperature (cooling) --> forward reaction is favored ---> K increases
Note that temperature is the only factor that changes K (and not Q).
increase temperature--> increases K --> the forward reaction is favored (reaction shifts to the right)
decrease temperature --> decrease K --> reverse reaction is favored
For exothermic reaction (delta H is negative, the reverse reaction is endothermic and requires energy while the forward reaction releases energy):
increase temperature --> reverse reaction is favored --> K decreases
decrease temperature (cooling) --> forward reaction is favored ---> K increases
Note that temperature is the only factor that changes K (and not Q).
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Re: Temperature
Temperature is the only condition that changes K. There are two different types of temperatures that can change K: exothermic and endothermic.
If the reaction is endothermic, you will be given a delta H > 0, showing that you need to add energy to make the reaction go forward. For that reason, if you increase the temperature with an endothermic reaction, K will increase since the forward reaction is favored (more products form). If you decrease the temperature, K decreases as the reverse reaction is formed (more reactants are formed -- the denominator increases, decreasing K). For exothermic reactions, delta H < 0, so the opposite is true. If you increase the temperature, the reverse reaction is formed (more reactants are formed -- the denominator increases, K decreases).
If the reaction is endothermic, you will be given a delta H > 0, showing that you need to add energy to make the reaction go forward. For that reason, if you increase the temperature with an endothermic reaction, K will increase since the forward reaction is favored (more products form). If you decrease the temperature, K decreases as the reverse reaction is formed (more reactants are formed -- the denominator increases, decreasing K). For exothermic reactions, delta H < 0, so the opposite is true. If you increase the temperature, the reverse reaction is formed (more reactants are formed -- the denominator increases, K decreases).
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Re: Temperature
The question will likely tell you what delta H is and you can use this to determine whether the reaction is endothermic or exothermic and how it will react to changes in temperature. If the question doesn’t give you a value for delta H, a general trend is that when you’re forming bonds, you release energy (exothermic) and when you break bonds you require energy (endothermic). If the reaction is exothermic, increasing heat will favor the reverse reaction, and if the reaction is endothermic, increasing heat will favor the forward reaction. Hope this helps!
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Re: Temperature
We need to first determine whether the forward/reverse reaction is endothermic/exothermic. If the forward reaction is endothermic, then increasing the temperature will shift the reaction in the forward direction, hence K will increase; if the forward reaction is exothermic, then K will decrease.
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Re: Temperature
Why does temperature change K and not Q values? or does temperature alter the conditions of the reaction enough that K is different?
If the second is true, why would Q remain constant?
If the second is true, why would Q remain constant?
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Re: Temperature
A reaction will favor either products or reactants if it is heated or cooled based on whether the forward reaction is endothermic or exothermic. When the forward reaction is endothermic, the reverse reaction is exothermic and vice versa. When endothermic forward reactions are heated, the products are favored. When exothermic forward reactions are heated, the reactants are favored. Hope this helps!
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Re: Temperature
If delta H is positive, the reaction is endothermic and requires heat, which would favor product formation. If delta H is negative, the reaction is exothermic and gives off heat, which favors reactant formation. Hope this helps!
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Re: Temperature
In order to be able to answer that question, you would also have to be given whether the reaction is exothermic or endothermic. Another possibility is that you will be given a Delta H. If you Delta H value is positive, it means that favors products because the reaction is endothermic. If Delta H is negative, it means that reactants will be favored since the reaction is exothermic.
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Re: Temperature
You would need to know whether the reaction is exothermic or endothermic, thus determining whether heat is a reactant or product within that rxn.
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Re: Temperature
You'll need to know if the reaction is exothermic or endothermic, which depends on the delta H.
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Re: Temperature
I believe we would just need to state if the reaction is end or exothermic. The response depends on delta h
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Re: Temperature
You would need to determine whether the reaction is endothermic or exothermic which is given by looking at the value of delta H.
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Re: Temperature
We would be able to tell if the reaction prefers reactants or products based on if the reaction is exothermic (delta H is negative) or endothermic (delta H is positive).
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Re: Temperature
You would need to know whether the reaction is endo or exothermic in order to answer this.
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Re: Temperature
Hello! It is likely that the question will indicate the value of delta H which you will be able to use to determine whether or not the reaction itself is endothermic or exothermic. In essence, finding out whether it is an endothermic or exothermic reaction, should display how the reaction will respond to changes in temperature. Also, in the case that delta H is not provided in the question, you should be able to determine whether or not the reaction is exothermic by checking for released energy in the form of bonds that had been formed.
Re: Temperature
like others have said in the post, the temperature definitely impacts which side is favored and this depends on if the reaction is endothermic or exothermic. Basically you have to see which side is something (in this case temperature) added and that will push reaction to the other side.
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Re: Temperature
Because k does change when there's a change in temperature, products are favored during an endothermic reaction and reactants are favored during an exothermic reaction.
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Re: Temperature
I believe it would be critical to determine if the reaction is endothermic or exothermic for this rxn
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Re: Temperature
We need to know if this reaction is endothermic or exothermic. If it's endothermic, delta H is positive, and the reaction gains energy. If it's exothermic, delta H is negative, and the reaction releases energy.
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Re: Temperature
We would have to be given the delta H value which would tell us if the reaction is endothermic or exothermic.
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Re: Temperature
We would need to know if the reaction is endothermic or exothermic. Then, we could determine which it favors based on the change in temperature.
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Re: Temperature
We would need to know delta H in order to determine whether or not the reaction is endothermic or exothermic. If delta H is positive, the reaction is positive, the reaction is endothermic, whereas if delta H is negative, the reaction is exothermic.
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Re: Temperature
If the reaction is exothermic, than increasing the temperature would favor reactants and vice versa.
Re: Temperature
if the reaction is endothermic it will favor the product formation and if the reaction is exothermic the reaction will favor the reactant formation.
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Re: Temperature
You need to know the sign of deltaH (whether the reaction is exothermic or endothermic) to determine this. This should be given to you in a problem.
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Re: Temperature
To figure this out, you have to determine if the reaction is endothermic or exothermic based on the enthalpy value. If it's endothermic the reaction will shift to the right and if it's exothermic, the reaction will shift to the left.
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Re: Temperature
If a reaction is exothermic (negative) raising the temperature will tend to shift the reaction towards reactants, if the reaction is endothermic (positive) is shifting towards products to happen
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Re: Temperature
We will be given the enthalpy (delta H). From that, we will be expected to know if the reaction is endothermic or exothermic. Then, we will have to know which way the reaction proceeds based on the change. They can also ask whether K will increase or decrease due to the temperature change.
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Re: Temperature
If a reaction is endothermic, then it will favor product formation because more reactant is added. If a reaction is exothermic, then it will favor reactant formation because more product is added.
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Re: Temperature
This would depend on whether the rxn is exothermic or endothermic. You would be asked in relation to this.
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Re: Temperature
We might get the delta H and be asked what would be favored if there was a temperature increase/decrease.
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