endo/exo and temp

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dtolentino1E
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endo/exo and temp

Postby dtolentino1E » Sun Feb 16, 2020 2:22 pm

why do exothermic reactions shift to reactants and endothermic reactions shift to products when there is an increase in temperature?

Lara Kristine Bacasen 1L
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Re: endo/exo and temp

Postby Lara Kristine Bacasen 1L » Sun Feb 16, 2020 2:32 pm

So for an exothermic reaction, energy is given off and thus makes the value negative. When you increase the temperature it puts energy into the system causing it to favor an endothermic reaction which is the revers. Thus the equilibrium will shift left. It's the same thinking for Endothermic reactions, since energy is being put into the system with the increase in temperature it will favor the forward reaction and thus shift right to the products.

Charysa Santos 4G
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Re: endo/exo and temp

Postby Charysa Santos 4G » Sun Feb 16, 2020 2:48 pm

Think of energy/heat being a reactant in endothermic reactions (heat must be supplied), and as a product in exothermic reactions (heat is being released). So when you increase temperature in an endothermic reaction, you are increasing the amount of reactants so the reaction will favor the products, and if you increase temperature in an exothermic reaction, you are increasing the amount of products, so the reaction will favor the reactants.

Amy Kumar 1I
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Re: endo/exo and temp

Postby Amy Kumar 1I » Sun Feb 16, 2020 8:01 pm

In endothermic reactions, heat is like a reactant. This means that if heat is added, there are more reactants, which means that reaction will shift towards the products in the forward direction.

Amanda Mei 1B
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Re: endo/exo and temp

Postby Amanda Mei 1B » Sun Feb 16, 2020 8:12 pm

Think of heat as either a reactant being absorbed by the reaction (endothermic) or product being given off the reaction (exothermic). If temperature is increased, the reaction will shift away from the side that the heat is on. If temperature is decreased, heat will shift to that side.

BCaballero_4F
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Re: endo/exo and temp

Postby BCaballero_4F » Sun Feb 16, 2020 8:29 pm

You can look at adding heat as adding a product or reactant depending on whether it is exothermic or endothermic. If you are adding a product, then it will shift to reactants, and vice versa.

kendal mccarthy
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Re: endo/exo and temp

Postby kendal mccarthy » Sun Feb 16, 2020 9:33 pm

Treat heat as another product or reactant. When I know a reaction is exothermic I write heat on the product side, as exothermic releases heat. If I know a reaction is endothermic I write heat on the reactant side. Then treat heat as you would a product or reactant.

ex. if a reaction has an increase in the concentration of one product it will proceed toward the reactant side to reestablish equilibrium. follow the same guidelines just intead of concentrations use increase or decrease of heat in either exothermic or endothermic reactions.

VioletKo3F
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Re: endo/exo and temp

Postby VioletKo3F » Sun Feb 16, 2020 9:47 pm

Exothermic reactions produce heat. When the temperature is raised, there is more heat (product) so the system shifts to the reactants to maintain the equilibrium.

Nikki Razal 1L
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Re: endo/exo and temp

Postby Nikki Razal 1L » Sun Feb 16, 2020 10:10 pm

the way i think abt is where heat is placed when it's written in a chemical rxn, when the rxn is endothermic, heat is on the left, and when it's exothermic it's on the left (you can think of this happening bc when heat is released, it is written as -)

Mai V 4L
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Re: endo/exo and temp

Postby Mai V 4L » Mon Mar 09, 2020 2:21 pm

Does anyone have a chart/trick for remembering this?

WGaines_2E
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Re: endo/exo and temp

Postby WGaines_2E » Tue Mar 10, 2020 8:46 pm

in exothermic reactions, heat is a product. So when heat is added, it caused the reaction to shift in favor of reactants

William Chan 1D
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Re: endo/exo and temp

Postby William Chan 1D » Wed Mar 11, 2020 10:21 pm

Using Le Chatlier's principle to simplify things, we can imagine heat as either a reactant or a product.
In an exothermic reaction, heat can be treated as a product because heat is given off during an exothermic reaction. By increasing temperature, we are essentially increasing the heat available in the system, so the reaction will shift to the left.
In an endothermic reaction, heat can be treated as a reactant. By increasing the temperature, we are increasing the heat available, and thus the reaction will shift to the right.

Bryan Chen 1H
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Re: endo/exo and temp

Postby Bryan Chen 1H » Wed Mar 11, 2020 10:27 pm

in these problems i tend to think of heat as a reactant (endothermic) or product (exothermic). Then depending on an increase or decrease in temp, I use le chatelier's principle treating heat as a R or P


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