Use this observed pattern to predict the number of energy levels in a neutral atom:
rb - rubidium (atomic number 37)
cs - cesium (atomic number 55)
fr - francium (atomic number 87)
ni - nickel (atomic number 28)
hg - mercury (atomic number 80)
kr - krypton (atomic number 36)

#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.