Temperature

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Lily Mohtashami
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Temperature

Postby Lily Mohtashami » Wed Jan 13, 2021 10:52 am

How would we be asked whether a reaction favors products or reactants based on temperature?

Q Scarborough 1b
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Re: Temperature

Postby Q Scarborough 1b » Wed Jan 13, 2021 10:53 am

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.

Sreeram Kurada 3H
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Re: Temperature

Postby Sreeram Kurada 3H » Wed Jan 13, 2021 10:55 am

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.

Charlotte Adams 1A
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Re: Temperature

Postby Charlotte Adams 1A » Wed Jan 13, 2021 11:10 am

We would need to be given if the reaction is endothermic or exothermic. I assume we will either by told or given delta h.

Biona Hui 1G
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Re: Temperature

Postby Biona Hui 1G » Wed Jan 13, 2021 11:43 am

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).

Aayushi Jani 3A
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Re: Temperature

Postby Aayushi Jani 3A » Wed Jan 13, 2021 12:51 pm

Yes, as others stated above, you would need to know whether the reaction is endothermic or exothermic (given by delta h).

Mursall M 2A
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Re: Temperature

Postby Mursall M 2A » Wed Jan 13, 2021 12:56 pm

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!

VincentLe_3A
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Re: Temperature

Postby VincentLe_3A » Wed Jan 13, 2021 3:23 pm

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.

DMaya_2G
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Re: Temperature

Postby DMaya_2G » Wed Jan 13, 2021 5:32 pm

We need to know if the reaction is endothermic or exothermic, which is given by delta h.

Katie Le 3K
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Re: Temperature

Postby Katie Le 3K » Wed Jan 13, 2021 6:03 pm

Based on if the rxn is endo or exothermic, we can use temperature to find which side the rxn favors

Maya Johnson 2a
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Re: Temperature

Postby Maya Johnson 2a » Wed Jan 13, 2021 7:26 pm

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

Megan ODonnell 3F
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Re: Temperature

Postby Megan ODonnell 3F » Wed Jan 13, 2021 7:32 pm

We would be asked a question regarding temperature given context on the enthalpy and whether the reaction is endothermic or exothermic.

Mackenzie Stockton 2H
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Re: Temperature

Postby Mackenzie Stockton 2H » Fri Jan 15, 2021 11:34 am

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).

Samantha Lee 1A
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Re: Temperature

Postby Samantha Lee 1A » Fri Jan 15, 2021 2:06 pm

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).

Alexandra Ahlschlager 1L
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Re: Temperature

Postby Alexandra Ahlschlager 1L » Fri Jan 15, 2021 3:14 pm

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!

Jiapeng Han 1C
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Re: Temperature

Postby Jiapeng Han 1C » Fri Jan 15, 2021 11:35 pm

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.

Ayesha Aslam-Mir 3C
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Re: Temperature

Postby Ayesha Aslam-Mir 3C » Sun Jan 17, 2021 3:29 am

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?

Carly_Lipschitz_3H
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Re: Temperature

Postby Carly_Lipschitz_3H » Sun Jan 17, 2021 9:24 am

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!

OmarArafat_2K
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Re: Temperature

Postby OmarArafat_2K » Sun Jan 17, 2021 9:46 am

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!

Kiana Tashakori 1D
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Re: Temperature

Postby Kiana Tashakori 1D » Sun Jan 17, 2021 4:53 pm

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.

Britney Tran IJ
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Re: Temperature

Postby Britney Tran IJ » Sun Jan 17, 2021 5:08 pm

You would need to know whether the reaction is exothermic or endothermic, thus determining whether heat is a reactant or product within that rxn.

Jordi M 2I
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Re: Temperature

Postby Jordi M 2I » Sun Jan 17, 2021 5:09 pm

Based on a given enthalpy (usually seen as delta h)

Justin Zhang_1A
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Re: Temperature

Postby Justin Zhang_1A » Sun Jan 17, 2021 5:27 pm

You'll need to know if the reaction is exothermic or endothermic, which depends on the delta H.

DavidTabib 3H
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Re: Temperature

Postby DavidTabib 3H » Sun Jan 17, 2021 5:56 pm

The delta H says where the reaction is endothermic or exothermic

Naomi Hernandez-Ramirez 1J
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Re: Temperature

Postby Naomi Hernandez-Ramirez 1J » Sun Jan 17, 2021 6:57 pm

I believe we would just need to state if the reaction is end or exothermic. The response depends on delta h

Anthony_Sandoval_1D
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Re: Temperature

Postby Anthony_Sandoval_1D » Sun Jan 17, 2021 10:35 pm

You would need to determine whether the reaction is endothermic or exothermic which is given by looking at the value of delta H.

Linette Choi 3L
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Re: Temperature

Postby Linette Choi 3L » Sun Jan 17, 2021 10:44 pm

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).

Jack_Pearce_2H
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Re: Temperature

Postby Jack_Pearce_2H » Sun Jan 17, 2021 10:47 pm

You would need to know whether the reaction is endo or exothermic in order to answer this.

Armen_Isayan_2L
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Re: Temperature

Postby Armen_Isayan_2L » Sun Jan 17, 2021 10:52 pm

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.

t_rasul2I
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Re: Temperature

Postby t_rasul2I » Sun Jan 17, 2021 11:30 pm

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.

Caelin Brenninkmeijer 1G
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Re: Temperature

Postby Caelin Brenninkmeijer 1G » Sun Jan 17, 2021 11:54 pm

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.

Gabe_Ek 1G
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Re: Temperature

Postby Gabe_Ek 1G » Sun Jan 17, 2021 11:56 pm

I believe it would be critical to determine if the reaction is endothermic or exothermic for this rxn

Zihan Liu 2K
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Re: Temperature

Postby Zihan Liu 2K » Mon Jan 18, 2021 12:09 am

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.

Nicoli Peiris 1B
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Re: Temperature

Postby Nicoli Peiris 1B » Mon Jan 18, 2021 11:49 am

We would have to be given the delta H value which would tell us if the reaction is endothermic or exothermic.

Sejal Parsi 3K
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Re: Temperature

Postby Sejal Parsi 3K » Tue Jan 19, 2021 1:54 am

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.

Madeline Ogden 3B
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Re: Temperature

Postby Madeline Ogden 3B » Tue Jan 19, 2021 12:32 pm

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.

Annika Tamaki 1E
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Re: Temperature

Postby Annika Tamaki 1E » Tue Jan 19, 2021 12:55 pm

If the reaction is exothermic, than increasing the temperature would favor reactants and vice versa.

emwoodc
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Re: Temperature

Postby emwoodc » Wed Jan 20, 2021 7:54 pm

if the reaction is endothermic it will favor the product formation and if the reaction is exothermic the reaction will favor the reactant formation.

jessicasilverstein1F
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Re: Temperature

Postby jessicasilverstein1F » Thu Jan 21, 2021 7:12 pm

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.

Lung Sheng Liang 3J
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Re: Temperature

Postby Lung Sheng Liang 3J » Fri Jan 22, 2021 11:05 pm

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.

Ellison Gonzales 1H
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Re: Temperature

Postby Ellison Gonzales 1H » Sat Jan 23, 2021 9:34 pm

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

chinmayeec 2H
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Re: Temperature

Postby chinmayeec 2H » Sat Jan 23, 2021 10:21 pm

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.

Mingzi Yang 1E
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Re: Temperature

Postby Mingzi Yang 1E » Sun Jan 24, 2021 6:12 pm

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.

Muskaan Abdul-Sattar
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Re: Temperature

Postby Muskaan Abdul-Sattar » Sun Jan 24, 2021 6:35 pm

This would depend on whether the rxn is exothermic or endothermic. You would be asked in relation to this.

Charlotte Adams 1A
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Re: Temperature

Postby Charlotte Adams 1A » Sun Jan 24, 2021 6:37 pm

We might get the delta H and be asked what would be favored if there was a temperature increase/decrease.

Sukhkiran Kaur 3I
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Re: Temperature

Postby Sukhkiran Kaur 3I » Sun Jan 24, 2021 6:46 pm

We would need to know whether the reaction is endothermic or exothermic.


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