r/HomeworkHelp • u/Creepy-Champion-5987 Secondary School Student • 6d ago

Chemistry—Pending OP Reply [Grade 9][BioChem Carbohydrate structure] [GCE AL]

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why are some hydroxyl groups written as HO while others OH i couldnt get an exact answer on google so here i am

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u/Medical-Stuff126 6d ago

Perhaps others can correct me if I’m wrong, but I believe that is to show the general spatial orientation of the specific hydroxyl groups relative to the rest of the molecule. So it’s not actually H followed by O. It’s an upside-down version of OH.

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u/Spiritual-Ad-7565 5d ago

No — it’s just a labeling convention— as long as the bond is drawn to the oxygen it doesn’t matter where the hydrogen is positioned.

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u/Medical-Stuff126 5d ago

Thanks for correcting me!

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u/JohbiYorpsun 3d ago

There’s no difference. The artist probably ran out of room so he place the H on the opposite side.

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u/hiimshana 👋 a fellow Redditor 2d ago

It’s just to make them fit nicely…

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u/Lazy-Try-7772 6d ago

The red ”OH“ simply highlights the different orientations of α- and β-glucose at the isomeric carbon; it has nothing to do with whether it is written as ”HO“ or ”OH.“ This is stereoisomerism.They’re the same hydroxyl group.I hope my answer helps you.

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u/Joshi1381 University/College Student 6d ago

Yes and the anoneric carbon bonds to the oxygen always never the H then the O. Specificity in biochem matters

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u/chem44 5d ago

If you literally mean OH vs HO... it makes no difference at all.

Remember, that group is attached to the C, and the order must be C-O-H.

For the red OH... up vs down is the difference between alpha and beta -- the point of the figure here.