Chemistry What Is the Optimum Orientation of a Molecule?

[devilkidjin]

what exactly is that?

 

[GCT]

what exactly are you referring to? Within the medium, the surface area?

 

[devilkidjin]

i mean like the bonding of the carbon to the hydrogen etc...

like angle between

 

[GCT]

well this relates a lot to quantum models, but you can get an idea (albeit a very simplistic perspective) of the overall geometry simply based on a charge-charge attractions and repulsions. A simple explanation should be in your text.

 

[devilkidjin]

oh i must be asking the question wrong
like the chain of carbon would be like zig zag

so what would the optimum orientation
not the placement of the electrons with the quantum numbers/ model

 

[movies]

depends on the substituents on the atoms and the stereochemistry. In general you try to minimize gauche interactions of adjacent carbons first, then it gets more complicated if things start wrapping back onto themselves. These interactions can be on the smallish side where energy is concerned, so it's not hard to occupy the non-ground state conformations.

 

[GCT]

well any configuration ultimately has to do with quantum models, if you're referring to "stable" isomers and relative free energies (or enthalpies), there are chemical methods to distinguish the most stable configuration; thermodynamic considerations such as enthalpy of combustion, experiments associated with equilibrium concentrations, rate constants and more.

 

[devilkidjin]

k, but just for example how you figure out angle between CO2
like the bonds 120 degree? or how to get it

 

[GCT]

I see what you're getting at, is this a homework question? Ever heard of VSEPR? Lewis structures?

 

[devilkidjin]

yea, oh i think i got it
so like a trigonal planar would have angles 120 degree between them?

 

[devilkidjin]

thanks for all your hlep GCT

 

[GCT]

Sure thing, next time you might want to post such questions as homework...in the homework forum, that way people will know what you're referring to.