What is the atomic symbol for an isotope with protons = 27 and
atomic mass =
60?

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation:

Which element has the lowest electronegativity? calcium(ca) gallium(ga) selenium(se) bromine(br)

#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.