Which of these elements has the highest electronegativity A) lithium
B) nitrogen
C) potassium
D) arsenic
E) beryllium

#7 how does the structure of amino acids allow them to form a polypeptide? each amino acid has an amino group and a carboxyl group. each amino acid has a hydrogen atom and a carboxyl group. each amino acid has a carboxyl group and an r group. each amino acid has an r group and a hydrogen atom.