In the periodic table of chemical elements, the atoms of the same main group have a larger radius and a larger mass, and the mass of potassium is greater than sodium, but the radius is smaller than sodium. this means? ['Atomic radius is proportional to mass.', 'Atomic radius determines the mass.', 'The arrangement of potassium and sodium is a special case in the periodic table of the chemical elements.', 'Atomic mass determines radius.']