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Old 07-27-2009, 06:33 AM
Astronut Astronut is offline
Join Date: Jul 2009
Posts: 41
Default Re: The Space Shuttle and the ISS are a Hoax!

Originally Posted by galexander View Post
You just never give up do you Astronut? However you do have a tendency to misquote.

Who said anything about breaking titanium atoms apart? Are you talking about nuclear fission Astronut?
I copied everything you said to the letter, I never misquoted you. You, however, are either deliberately distorting what I said or you're more ignorant than I thought. I am NOT talking about nuclear fission, when I say "breaking titanium atoms apart" I'm talking about breaking them apart from EACH OTHER, I'm talking about breaking bonds, not the atoms themselves. I thought that was pretty obvious, but apparently I have to spoon feed you every word I say or else you'll misunderstand it just like you did the wiki article about bond dissociation energy.
It was actually Wikipedia which spoke of "Bond dissociation energy" while explaining what "Bond energy" was. I suggest you reread the quote carefully:
The article was actually titled bond dissociation energy for a reason; that's what it's talking about, and it even explicitly uses the words "bond dissociation energy" (as previously mentioned, equal to delta H on my graph) in your quote. You just proved my point, thanks for pointing it out again.
"Another example: an OH bond of a water molecule (HOH) has 493.4 kJ mol-1 of bond dissociation energy, and 424.4 kJ mol-1 is needed to cleave the remaining OH bond. The BOND ENERGY of the OH bonds in water is 458.9 kJ mol-1, which is the average of the values."
In case you didn't notice (obviously you're too busy quote mining), the bond energy it's talking about here is the average bond dissociation energy of the entire molecule and has nothing to do with the activation energy required to start breaking the bond, only the average net energy absorbed by the entire process. Take a college chemistry class, then maybe you'll know the difference between dissociation energies and the actual energy required to start breaking bonds. They are not the same, as I've demonstrated over and over. Ignoring it won't change the truth. Here's a little homework assignment for you; find out the "bond energy" of H2 and O2 diatomic species, then add those values in the correct proportions (half of O2 to one of H2) to the negative of 458.9 times two (to get the value for both bonds in H2O). If the result is negative you have an exothermic reaction, and indeed you do, so why don't the bonds of H2 and O2 spontaneously break and reunite as H2O at room temperature, or in the presence of UV light? It's energetically favorable, but it doesn't spontaneously occur even when there's ample amounts of reactants because you still must overcome the required activation energy, which isn't present at room temperature and isn't given by the average bond dissociation energy.
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