Enthalpy of a combustion reaction?

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Riya Sood 4G
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Enthalpy of a combustion reaction?

Postby Riya Sood 4G » Sat Feb 08, 2020 8:57 am

Is Delta H positive or negative for a combustion reaction?

Zoe Gleason 4F
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Joined: Tue Jul 23, 2019 12:15 am

Re: Enthalpy of a combustion reaction?

Postby Zoe Gleason 4F » Sat Feb 08, 2020 10:29 am

Since combustion reactions release a lot of heat, their ΔH will be negative.

Lara Kristine Bacasen 1L
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Re: Enthalpy of a combustion reaction?

Postby Lara Kristine Bacasen 1L » Sat Feb 08, 2020 11:42 am

Combustion is an exothermic reaction and gives off heat so the delta H should be negative.

Nicholas_Gladkov_2J
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Re: Enthalpy of a combustion reaction?

Postby Nicholas_Gladkov_2J » Sat Feb 08, 2020 11:47 am

Riya Sood 4G wrote:Is Delta H positive or negative for a combustion reaction?


If delta H is positive, this means that heat was absorbed in the chemical reaction (endothermic), and thus the surroundings loose heat, or become cold.
The opposite is true for negative delta H. This means that heat was released in the chemical reaction (exothermic), and thus the surroundings gain heat, or become hot.
Think of combustion as burning, so if you think about it, it is exothermic.

Madeline Phan 1E
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Re: Enthalpy of a combustion reaction?

Postby Madeline Phan 1E » Sat Feb 08, 2020 11:47 am

Combustion is an exothermic reaction, so delta H should be negative.

Nuoya Jiang
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Re: Enthalpy of a combustion reaction?

Postby Nuoya Jiang » Sat Feb 08, 2020 11:48 am

It is usually negative because heat is released during the combustion process.

305385703
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Re: Enthalpy of a combustion reaction?

Postby 305385703 » Sun Feb 09, 2020 7:01 pm

delta H is negative. Heat is being released as the products are entering a more stable state as they form reactants.

Max Madrzyk Dis 4G
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Re: Enthalpy of a combustion reaction?

Postby Max Madrzyk Dis 4G » Sun Feb 09, 2020 7:16 pm

Usually in a combustion reaction heat is released meaning that delta H will be negative.


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