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Enthalpy of a combustion reaction?

Posted: Sat Feb 08, 2020 8:57 am
by Riya Sood 4G
Is Delta H positive or negative for a combustion reaction?

Re: Enthalpy of a combustion reaction?

Posted: Sat Feb 08, 2020 10:29 am
by Zoe Gleason 4F
Since combustion reactions release a lot of heat, their ΔH will be negative.

Re: Enthalpy of a combustion reaction?

Posted: Sat Feb 08, 2020 11:42 am
by Lara Kristine Bacasen 1L
Combustion is an exothermic reaction and gives off heat so the delta H should be negative.

Re: Enthalpy of a combustion reaction?

Posted: Sat Feb 08, 2020 11:47 am
by Nicholas_Gladkov_2J
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.

Re: Enthalpy of a combustion reaction?

Posted: Sat Feb 08, 2020 11:47 am
by Madeline Phan 1E
Combustion is an exothermic reaction, so delta H should be negative.

Re: Enthalpy of a combustion reaction?

Posted: Sat Feb 08, 2020 11:48 am
by Nuoya Jiang
It is usually negative because heat is released during the combustion process.

Re: Enthalpy of a combustion reaction?

Posted: Sun Feb 09, 2020 7:01 pm
by 305385703
delta H is negative. Heat is being released as the products are entering a more stable state as they form reactants.

Re: Enthalpy of a combustion reaction?

Posted: Sun Feb 09, 2020 7:16 pm
by Max Madrzyk Dis 4G
Usually in a combustion reaction heat is released meaning that delta H will be negative.