Bond angles in molecules with double and triple bonds

[rainingspiders]

I know how to find out the molecular geometry and its corresponding bond angles when all the bonds are single bonds, but how much does a double and triple bond affect the bond angles? What if there is more than one double or triple bond? Or if a molecule as a double AND a triple bond?

 

Thanks!

[hypervalent_iodine]

You treat them the same as single bonds in this context. Some textbooks just call them electron sets or places where there are bonding electrons.

[AndresKiani]

I know how to find out the molecular geometry and its corresponding bond angles when all the bonds are single bonds, but how much does a double and triple bond affect the bond angles? What if there is more than one double or triple bond? Or if a molecule as a double AND a triple bond?

 

Thanks!

 

I'm going to assume your talking about carbon based molecules however this can apply to any covalent electron geometry.

 

If there are 4 electron domains (bonding and non-bonding) - 109.5⁰ , 3 electron domains 120⁰ , and 2 electron domains 180⁰

 

Now the specific experimentally observe data shows that for each molecule there is an error range in these standards of about +- 3 or 4, however this is pretty accurate.

 

So now taking to what we just established.. a double bonded region in a molecule has 3 electron domains in the central atom thus it's 120 degree geometry. As well, we can use this standard guideline to predict triple bonds as well, which have 2 electron domains, and so assume a 180 degree geometry.

 

The only exception is if there are 2 atoms in the molecule than the geometry is always going to be linear

[rainingspiders]

thanks!