How does adding an atom affect the position of existing atoms or lone pairs?

Adding an atom will increase the repulsion between existing atoms and lone pairs. Added atom will result in bond pair-bond pair and bond pair-lone pair repulsion. The magnitude of the lone pair-bond pair repulsion is greater than the bond pair-bond pair repulsion. The added atom will change the electron geometry and bring about a distortion in the molecular geometry.

the addition of another atom changes the geometry of the molecule

Explanation:

Bond electron pairs and lone electron pairs always repel each other because electrons have the same charge (negative charge). Therefore, they tend to stay far away as possible. This gives the molecule a unique geometry. Then if we add another atom to this molecule, the geometry changes again to minimize the repulsion.

Further explanation:  

In a molecule all the bond electron pairs and lone electron pairs repel each other because they have the same negative charge.  

Therefore, these electron pairs tend to stay as far as possible, giving the molecule a unique geometry.  

If we are going to add one more atom to this molecule, it means there comes another bond electron pair.  

Then the existing bond and lone electron pairs tend to repel the new bond electron pair as well.  

As a result, the geometry of the molecule changes in order to minimize the strain caused by repulsion.  

Learn more:  

1. Molecular geometry  : : Answered by Sarajevo

2. Electron pair repulsions : : Answered by KaptainEasy

Key words: geometry, bond pair, lone pair, repulsion, electrons

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