S Vs R Configuration Question

[SyrianHero]

If a molecule is determined to be in an S configuration, and molecules obviously move and rotate in space, I'm confused why that same molecule after rotating and moving in space can't appear in the R configuration. If you have a molecule that is made up of one carbon and 4 different groups attached to it, it seems like if the molecule rotated in space its configuration would change. Why is this wrong?

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[Optimist Prime]

Because no matter how the molecule turns and moves it space the molecules are still in the same orientation with respects to one another. If you draw two molecules and flip one from the other you will see that if the first one was R the second one will also be R because say if you had Br in front and Cl in back. When you flipped it you would have CL in front and Br in back and although those moved in space they still have the same orientation from one another. Also it would cause the other two molecules attached to also flip.

 

[Optimist Prime]

Sorry if that didn't make any sense its hard for me to teach concepts through a computer that I would normally have to draw out

 

[PassEdge]

It's a chirality thing. Can you take a right hand baseball glove and stick it to fit on your left hand? No.

Here, the right hand baseball glove would be the R configuration molecule, and your left hand would be the S.

 

[Necr0sis713]

Just try drawing an R config compound, and then rotate it and assign config again. No matter what way you rotate it, it will be R