1. I find these type of diagrams

    The glucose molecule structure

    easier to consult when building molecules using a 'molecular building kit'. Is there a name for this type of diagram?

  2. For the glucose molecule (in the above diagram), I noticed the order of H, and OH bonds are not in the same order (sometimes H to the left, and sometimes to the right). Does that represent anything? Will it change the way one would build this molecule using a kit?

  • $\begingroup$ The representation of the Fischer projection is not the standard presentation. Rotate your screen by 180 degrees. What is on the bottom should be on the top. This Fischer projection is of L-glucose not of THE glucose, D-glucose. To create D-glucose, switch the positions of the OH's and H's on the central four carbons. Better Fischer projections of D-glucose may be found on the internet. $\endgroup$ – user55119 Oct 24 '20 at 11:53

So the diagram your referring to is called a Fischer projection and represents the non-cyclic form of glucose (usually when glucose is in the presence of water, it reacts to form it’s cyclic structure).

When looking at the Fischer projection, take note of the four carbons in the middle of the linear structure. These are chiral carbon atoms. The way the other atoms are attached to the carbon atom matters. Switching the position of an H or OH group changes the geometrical orientation of that chiral center, making the molecule different.

To make this a little more clear, think about how you have a left and right hand. Although they appear the same, the way your fingers are attached matter, i.e. you can’t put your right hand into a lefty glove because of the way your fingers are attached to your hand.


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