Dipoles and determining molecular (a)symmetry [closed]








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What is a dipole? Also, how do you know if a molecule is symmetrical or asymmetrical?


For example, are the following symmetrical or asymmetrical? Can you tell just from the molecular formula? Which ones have dipoles?


* $\ce{O2}$
* $\ce{H2O}$
* $\ce{CO2}$


Are these concepts related?




You should easily find the answers by searching the web.


A dipole is the separation of a positive charge and a negative charge in a molecule. Any 2 different atoms bonded together will have a dipole since their electronegativities are different.


A symmetrical molecule will either have a mirror plane or a rotation that will superimpose the atoms. Benzene has both a mirror plane and a rotation of 60°.


An asymmetrical molecule does not have a mirror plane or rotation. Ethanol is an example.


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