guy
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Why is Pt a good catalyst?
Pt is widely know for catalyzing many reactions, especially with H2. My question is what makes it such a good catalyst? My chem teacher didn't know
why. I searched google and didn't find any explanation. I did however find that H2 can form complexes with metals. Is this the main reason for
catalystic properties of Pt metals? But then, why don't other transition metals catalyze H2 reactions if they all have the ability to adsorb H2?
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Twospoons
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Nickel will catalyse hydrogenation reactions. But Pt is better at it. Why? I don't know.
Helicopter: "helico" -> spiral, "pter" -> with wings
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Magpie
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IIRC catalysts work by providing a reaction route that requires less energy. I don't know the mechanics for how Pt works, however.
The single most important condition for a successful synthesis is good mixing - Nicodem
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guy
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I found a site(http://www.science.uwaterloo.ca/~cchieh/cact/applychem/heter...) that describes a little about how it works. All it said was that the Pt adsorbs
H2 and weakens the bonds.
It said other metals may attract H2 too much and not make the reaction work. Some how it said that metals farther left are stronger chemisorbers.
Why? they have larger radius and smaller electron affinity.
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guy
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This site better explains how hydrogen is chemisorbed to Pt.
http://www.library.uu.nl/digiarchief/dip/diss/2002-1028-1505...
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mick
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Catalytic hydrogenation is a 3 phase reaction. Gas, liquid and solid. The solid adsorbs the gas and the liquid makes it work.
mick
Typo
[Edited on 13-2-2006 by mick]
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