3 Methods

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Annalyn Diaz 1J
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3 Methods

Postby Annalyn Diaz 1J » Fri Jan 25, 2019 11:36 am

In lecture, Dr. Lavelle mentioned that using bind enthalpies is the least accurate method. Why is that so?

Dimitri Speron 1C
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Re: 3 Methods

Postby Dimitri Speron 1C » Fri Jan 25, 2019 1:44 pm

For bonds that are not from diatomic molecules, (molecules with 2 atoms) it is practically impossible to get a constant value for a bond that is found in many different molecules. For example, the carbon-carbon double bond is present in tons of different molecules and has a very slightly different bond enthalpy in each one. As such, the values given for non-diatomic bonds are just averages of the values from many different molecule types. Therefore they are somewhat less accurate.

Katelyn Phan 2A
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Re: 3 Methods

Postby Katelyn Phan 2A » Fri Jan 25, 2019 6:50 pm

The general reason is because the bond enthalpies for molecules that are not diatomic are averages depending on the different molecules they occur in.

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Re: 3 Methods

Postby LilyL1C » Fri Jan 25, 2019 8:03 pm

Bond enthalpies are the least accurate method because unless you are dealing with all diatomic elements, the values that you are using for delta H are averages, so these numbers will always be a little off. Therefore your final answer will also be a little off. Comparing this method to the other methods, it's less accurate.

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