Change in Temp

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Jessica Luong 3K
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Change in Temp

Postby Jessica Luong 3K » Sun Jan 10, 2021 11:59 pm

Is the enthalpy directly related to whether or not the reaction is endothermic or exothermic? For example, if enthalpy is positive then the reaction is always endothermic.

Lucy Wang 2J
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Re: Change in Temp

Postby Lucy Wang 2J » Mon Jan 11, 2021 12:18 am

yes when enthalpy is positive it's an endothermic reaction and when it is negative the reaction is exothermic

Simran Bains 2C
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Re: Change in Temp

Postby Simran Bains 2C » Mon Jan 11, 2021 3:13 am

Yes, I do believe that enthalpy determines whether a reaction is endothermic or exothermic.

Sara Sandri 2B
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Re: Change in Temp

Postby Sara Sandri 2B » Mon Jan 11, 2021 8:56 am

Yes. When the reaction';s enthalpy is positive, that means it requires more energy to occur than that which it releases. when a reaction's enthalpy is negative, that means that energy is released by the reaction more than is absorbed. In the context of chemical equilibrium, if temperature increases for a exothermic reaction, its K decreases because temperature always helps endothermic reactions (which is the reverse of an exothermic so the heat would help more reactants form). Contrarily, for an endothermic reaction where heat is added, K becomes larger because the forward reaction is the one that requires heat input and so more products will be formed.

sophie esherick 3H
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Re: Change in Temp

Postby sophie esherick 3H » Mon Jan 11, 2021 9:01 am

Yes, an endothermic reaction is one where the products have higher energy than the reactants, making it's enthalpy positive. For an exothermic reaction, the enthalpy is negative since it gives off heat, ending with products that have less energy than the reactants. Reverse reactions will have the opposite enthalpy sign. In chemical equilibrium, if you increase the heat of an endothermic reaction, it will favor the forward reaction. However, if you were to lower the temperature, the reverse reaction (exothermic) would be favored to produce more heat. Similarly, if you increase the temperature of an exothermic reaction, it will favor the reverse reaction (endothermic).

Nicoli Peiris 1B
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Re: Change in Temp

Postby Nicoli Peiris 1B » Mon Jan 11, 2021 12:09 pm

Yes! When enthalpy is positive it is endothermic. When it is negative it is exothermic.

Emmeline Phu 1G
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Re: Change in Temp

Postby Emmeline Phu 1G » Mon Jan 11, 2021 12:37 pm

Hi! Yes, enthalpy is directly related to whether the reaction is endothermic or exothermic. If the enthalpy is negative, then that means the reaction is exothermic and is releasing heat. If the enthalpy is positive, then that means the reaction is endothermic and is absorbing heat. Thus, with this information, we are able to figure out which direction the reaction will shift when heating or cooling it. Hope this helps! :)

Kareena Patel 1G
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Re: Change in Temp

Postby Kareena Patel 1G » Mon Jan 11, 2021 1:05 pm

Yes. If enthalpy is positive, it is endothermic. If enthalpy is negative, it is exothermic.

Gabriel Nitro 1E
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Re: Change in Temp

Postby Gabriel Nitro 1E » Mon Jan 11, 2021 1:26 pm

Hi,

Yes. If the enthalpy (delta H) is negative, the reaction is exothermic. If the enthalpy (delta H) is positive, the reaction is endothermic.

Hope this helps! :)

Jordan Tatang 3L
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Re: Change in Temp

Postby Jordan Tatang 3L » Mon Jan 11, 2021 1:37 pm

Yup + is endothermic and - is exothermic


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