Tungsten – Periodic Table – Atomic Properties

Tungsten-density-atomic-number-mass-radius

El tungsteno es un metal raro que se encuentra naturalmente en la Tierra casi exclusivamente en compuestos químicos. El tungsteno es un material intrínsecamente quebradizo y duro, lo que dificulta su trabajo.

Resumen

Elemento Tungsteno
Número atómico 74
Masa atómica [amu] 183,84
Masa atómica [pm] 162
Densidad en STP [g / cm3] 19.25
Numero de protones 74
Número de neutrones (isótopos típicos) 182-184, 186
Numero de electrones 74
Configuración electronica [Xe] 4f14 5d4 6s2
Estados de oxidación +6
Afinidad electrónica [kJ / mol] 78,6
Electronegatividad [escala de Pauling] 2,36
Primera energía de ionización [eV] 7,98

Número atómico: protones, electrones y neutrones en tungsteno

Proton Number - Atomic NumberEl tungsteno  es un elemento químico con número atómico  74, lo  que significa que hay 74 protones en su núcleo. Número total de protones en el núcleo se llama el  número atómico  del átomo y se le da el  símbolo Z . La carga eléctrica total del núcleo es, por tanto, + Ze, donde e (carga elemental) es igual a  1.602 x 10-19  culombios .

El número total de  neutrones  en el núcleo de un átomo se llama el  número de neutrones  del átomo y se le da el  símbolo N . Número de neutrones más el número atómico es igual al número de masa atómica:  N + Z = A . La diferencia entre el número de neutrones y el número atómico se conoce como  exceso de neutrones : D = N – Z = A – 2Z.

Para los elementos estables, suele haber una variedad de isótopos estables. Los isótopos  son nucleidos que tienen el mismo número atómico y, por lo tanto, son el mismo elemento, pero difieren en el número de neutrones. Los números de masa de isótopos típicos de  tungsteno  son  182-184, 186.

Masa atómica de tungsteno

La masa atómica del  tungsteno  es  183,84 u. 

The atomic mass is the mass of an atom. The atomic mass or relative isotopic mass refers to the mass of a single particle, and therefore is tied to a certain specific isotope of an element. The atomic mass is carried by the atomic nucleus, which occupies only about 10-12 of the total volume of the atom or less, but it contains all the positive charge and at least 99.95% of the total mass of the atom. Note that, each element may contain more isotopes, therefore this resulting atomic mass is calculated from naturally-occuring isotopes and their abundance.

Atomic Radius of Tungsten

The atomic radius of Tungsten atom is 162pm (covalent radius).

Atomic Radius of Chemical Elements

It must be noted, atoms lack a well-defined outer boundary. The atomic radius of a chemical element is a measure of the distance out to which the electron cloud extends from the nucleus. However, this assumes the atom to exhibit a spherical shape, which is only obeyed for atoms in vacuum or free space. Therefore, there are various non-equivalent definitions of atomic radius.

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 Tungsten is 74. 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 Tungsten is [Xe] 4f14 5d4 6s2.

Possible oxidation states are +6.

Density of Tungsten

Density of Tungsten is 19.25g/cm3.

Typical densities of various substances are at atmospheric pressure.

Density is defined as the mass per unit volume. It is an intensive property, which is mathematically defined as mass divided by volume:

ρ = m/V

Atomic Masses of Elements

Periodic Table of Elements - atomic mass

Atomic Radii of Elements

Periodic Table of Elements - atomic radius

Densities of Elements

Periodic Table of Elements - density

Tungsten-protons-neutrons-electrons-configuration

Tungsten-affinity-electronegativity-ionization

Electron Affinity – Tungsten

Electron affinity of Tungsten is 78.6 kJ/mol.

In chemistry and atomic physics, the electron affinity of an atom or molecule is defined as:

the change in energy (in kJ/mole) of a neutral atom or molecule (in the gaseous phase) when an electron is added to the atom to form a negative ion.

X + e → X + energy        Affinity = – ∆H

In other words, it can be expressed as the neutral atom’s likelihood of gaining an electron. Note that, ionization energies measure the tendency of a neutral atom to resist the loss of electrons. Electron affinities are more difficult to measure than ionization energies.

Electronegativity of Tungsten

Electronegativity of Tungsten is 2.36.

Electronegativity, symbol χ, is a chemical property that describes the tendency of an atom to attract electrons towards this atom. For this purposes, a dimensionless quantity the Pauling scale, symbol χ, is the most commonly used.

The electronegativity of Tungsten is: χ = 2.36

First Ionization Energy of Tungsten

First Ionization Energy of Tungsten is 7.98 eV.

Ionization energy, also called ionization potential, is the energy necessary to remove an electron from the neutral atom.

X + energy → X+ + e

where X is any atom or molecule capable of being ionized, X+ is that atom or molecule with an electron removed (positive ion), and e is the removed electron.

A Tungsten atom, for example, requires the following ionization energy to remove the outermost electron.

W + IE → W+ + e        IE = 7.98 eV

Electronegativity of Elements

Periodic Table of Elements - electronegativity

Ionization Energy of Elements

Periodic Table of Elements - ionization energy

Tungsten-periodic-table

Source: www.luciteria.com

 

Properties of other elements

Tungsten - Comparison of Atomic Properties

Periodic Table in 8K resolution

Other properties of Tungsten