The Amide Structure Is the Fundamental Linking Unit in Proteins

Essay

The amide structure is the fundamental linking unit in proteins. Two partial Lewis structures for formamide are shown below. These structures do not show the lone-pair electrons or the formal charges. Experiment shows that formamide is planar, so which is the better representation of the electronic structure, I or II? Is this conclusion consistent with the formal charges on the atoms? Explain the rationale for your answers.