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How to draw structural isomers with the molecular formula

how do you draw structural isomers of organic molecules with just the molecular formula? I'm struggling with organic chemistry in a levels and i dont really get how you draw out other structural isomers when given the molecular formula as cant you make them up yourselves?
Original post by kimpo078
how do you draw structural isomers of organic molecules with just the molecular formula? I'm struggling with organic chemistry in a levels and i dont really get how you draw out other structural isomers when given the molecular formula as cant you make them up yourselves?


Write out the molecular formula of the molecule you want to draw.
Determine the number of carbon atoms in the molecule.
Determine the number of double bonds or rings present in the molecule.
Use these clues to start drawing out the skeleton structure of the molecule, making sure to account for all of the atoms specified in the molecular formula.
Use the presence of double bonds or rings to guide the placement of the atoms and the connectivity of the skeleton structure.
Add any substituent groups or functional groups to the skeleton structure as necessary.
Check that your final drawing correctly represents the molecular formula and satisfies the constraints of the molecule (e.g., number of carbon atoms, presence of double bonds or rings).
It may be helpful to consult a table of common functional groups and their structures as you draw the isomers. You can also try drawing multiple different isomers and comparing them to see if they are distinct structures.

Hope this helps!!

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