Oxaloacetic acid, an important intermediate in food metabolism, has the formula c4h4o5 and contains three c=o bonds and two o-h bonds. propose the two most stable possible lewis structures. (show all lone pairs)

The most stable possible Lewis structures are in the picture

Explanation:

In the left of the picture are three C=O bonds and two O-H bond. By formula C₄H₄O₅ there are missing two hydrogens and one carbon that most be a methylene group (CH₂). Thus, the most logical ways to bond the substructures are drawing in the picture having in mind that O-O bond are not stable.

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