Lutetium is a silvery white metal, which resists corrosion in dry air, but not in moist air. Lutetium is the last element in the lanthanide series, and it is traditionally counted among the rare earths.
Protons and Neutrons in Lutetium
Lutetium is a chemical element with atomic number 71 which means there are 71 protons in its nucleus. Total number of protons in the nucleus is called the atomic number of the atom and is given the symbol Z. The total electrical charge of the nucleus is therefore +Ze, where e (elementary charge) equals to 1,602 x 10-19 coulombs.
The total number of neutrons in the nucleus of an atom is called the neutron number of the atom and is given the symbol N. Neutron number plus atomic number equals atomic mass number: N+Z=A. The difference between the neutron number and the atomic number is known as the neutron excess: D = N – Z = A – 2Z.
For stable elements, there is usually a variety of stable isotopes. Isotopes are nuclides that have the same atomic number and are therefore the same element, but differ in the number of neutrons. Mass numbers of typical isotopes of Lutetium are 175.
Main Isotopes of Lutetium
Lutetium occurs in 2 natural isotopes: 175Lu and 176Lu. 176Lu is very slightly radioactive, decaying by beta decay with a half-life of 3.78×1010 years. 175Lu is the most common isotope, having a natural abundance of approximately 97%.
Lutetium-175 is composed of 71 protons, 104 neutrons, and 71 electrons.
Lutetium-176 is composed of 71 protons, 105 neutrons, and 71 electrons.
Naturally Occuring Isotopes
Isotope | Abundance | Neutron Number |
175Lu | 97.401% | 104 |
176Lu (unstable) | 2.599% | 105 |
Typical Unstable Isotopes
Isotope | Half-life | Decay Mode | Product |
173Lu | 1.37 y | electron capture | 173Yb |
174Lu | 3.31 y | electron capture | 174Yb |
176Lu | 3.78×1010 y | beta decay | 176Hf |
Electrons and Electron Configuration
The number of electrons in an electrically-neutral atom is the same as the number of protons in the nucleus. Therefore, the number of electrons in neutral atom of Lutetium is 71. Each electron is influenced by the electric fields produced by the positive nuclear charge and the other (Z – 1) negative electrons in the atom.
Since the number of electrons and their arrangement are responsible for the chemical behavior of atoms, the atomic number identifies the various chemical elements. The configuration of these electrons follows from the principles of quantum mechanics. The number of electrons in each element’s electron shells, particularly the outermost valence shell, is the primary factor in determining its chemical bonding behavior. In the periodic table, the elements are listed in order of increasing atomic number Z.
Electron configuration of Lutetium is [Xe] 4f14 5d1 6s2.
Possible oxidation states are +3.
Summary
Element | Lutetium |
Number of protons | 71 |
Number of neutrons (typical isotopes) | 175 |
Number of electrons | 71 |
Electron configuration | [Xe] 4f14 5d1 6s2 |
Oxidation states | +3 |
Source: www.luciteria.com