Chapter 2 - Atoms, Molecules, and Ions - Questions and Exercises - Exercises - Page 85: 2.59

(a) representative (b) transition metal (c) representative (d) inner transition metal

(a) Xe, or xenon, is a representative element because it is a main-group element, meaning it is in the "A" group elements. Xenon is in group 8A of the periodic table. (b) Iron, or Fe, is a transition metal because it is in the middle section of the periodic table called the "B" section. Iron is in group 8B of the periodic table. (c) K, or potassium, is a representative element because it is a main-group element, meaning it is in the "A" group elements. Potassium is in group 1A of the periodic table. (d) Europium, or Eu, is an inner transition metal because it is in the series called the lanthanide series. Any element that follows either lanthanum or actinium is considered an inner transition metal.