Bond Enthalpy Method

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Anika Chakrabarti 1A
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Bond Enthalpy Method

Postby Anika Chakrabarti 1A » Sat Jan 25, 2020 7:36 pm

Why is using bond enthalpies to calculate H the least accurate method?

chrisleung-2J
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Re: Bond Enthalpy Method

Postby chrisleung-2J » Sat Jan 25, 2020 7:59 pm

This is because all bond enthalpies except those of diatomic molecules are averages from multiple molecule structures containing the bond, and thus may not be perfectly accurate reflections of the bond energy for a specific molecule which may have other species altering the bond in question.

PranaviKolla2B
Posts: 114
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Re: Bond Enthalpy Method

Postby PranaviKolla2B » Sat Jan 25, 2020 8:52 pm

What is the most accurate way to calculate H?

Sjeffrey_1C
Posts: 108
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Re: Bond Enthalpy Method

Postby Sjeffrey_1C » Sat Jan 25, 2020 8:54 pm

PranaviKolla2B wrote:What is the most accurate way to calculate H?


I assume Hess's method is most accurate.

Abigail_Hagen2G
Posts: 107
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Re: Bond Enthalpy Method

Postby Abigail_Hagen2G » Sat Jan 25, 2020 9:26 pm

Yes, Hess's Law should be the most accurate, it doesn't rely on averages

Maia_Jackson_2C
Posts: 101
Joined: Fri Aug 30, 2019 12:17 am

Re: Bond Enthalpy Method

Postby Maia_Jackson_2C » Sat Jan 25, 2020 10:04 pm

But why is Hess's method more accurate than the third method we learned?


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