How Many Valence Electrons Does Xenon (Xe) Have? [Valency of Xe]

Xenon, a chemical element with the symbol Xe and atomic number 54, is a colorless, odorless, tasteless, non-flammable, nontoxic inert gas. It is an extremely rare noble gas found on the earth's surface.

It is used in flash lamps, arc lamps, and also used as general anesthesia. Mostly noble gases do not react with other atoms but unlikely xenon readily reacts with fluorine to form different fluorides. XeF6, XeF4 and XeF2 are the three stable fluorides of xenon. XeF can be produced but theoretically, it is highly unstable. It can also reacts with chlorine, bromine, and iodine to form XeCl2, XeCl4, XeClF,  XeBr and XeI.

You are here to know valence electrons and valency of xenon, aren’t you? But before that let’s have some ideas about what these two terms are:

Difference Between Valence Electrons and Valency

Valence electrons are the total number of electrons present in the outermost shell of an atom (i.e. in outermost orbital). The valence electrons for a neutral atom is always definite, it cannot be varied (more or less) in any condition for a particular atom and may or may not be equal to its valency.

Valency is defined as the total number of electrons an atom can lose, gain, or share at the time of bond formation to get a stable electronic configuration i.e. to complete an octet. The valency of an atom can be variable in different compounds or chemical reactions due to the different bonding circumstances. Most of the time valency varies/changes due to change in oxidation and reduction states.

Xenon (Xe) Valence Electrons

There are four simple steps to find out the valence electrons for xenon atom which are:

Step 1: Find the Atomic Number

To find out the atomic number of xenon, we can use the periodic table. With the help of the periodic table, we can easily see that the atomic number of xenon is 54. As its atomic number is 54, it has 54 protons, and for neutral xenon, the number of protons is always equal to the number of electrons i.e. Xe has 54 electrons in its nucleus.

Step 2: Write Electron Configuration

Electron configuration is the arrangement of electrons on the orbitals. The xenon atom has a total of 54 electrons so, we have to put 54 electrons in orbitals. The electrons will be placed in orbital according to this energy levels: [1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f]. Now,

Xenon electron configuration Xe (54) = 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰5s²5p⁶ (complete configuration)

= [Kr]4d¹⁰5s²5p⁶ (condensed configuration).

Step3: Determine Valence Shell

As we know, the valence shell of an atom can be found from the highest number of principle quantum numbers which is expressed in the term of n, and in [Kr]4d¹⁰5s²5p⁶, the highest value of n is 5 so that the valence shell of Xe is 5s²5p⁶.

Step 4: Find Valence Electrons

The total number of electrons present in the valence shell of an atom is called valence electrons, and there is only one electron present in the valence shell of xenon (5s²5p⁶). Thus, xenon has eight valence electrons.

Valency of Xenon (Xe)

There are many different ways to find out the valency of an atom which reflects the ability of an atom to bond with other atoms. Valence describes how easily an atom or a free radical can combine with other chemical species. The valency of an atom is determined based on the number of electrons lost, gained, or shared with another atom at the time of bond formation.

An atom is said to be stable when its outermost shells have eight electrons (except H & He). If the total number of electrons in outermost shells is between one to four, the atom has positive valency and if electrons are between four to eight, the valency is calculated by subtracting from eight and valency will be zero. Atoms having four outermost electrons possess both positive and negative valency, and atoms having eight outermost electrons, valency will be zero (i.e. noble gases).

Noble gases like xenon have eight valence electrons so it does not require to lose or gain electrons to complete their energy shell i.e. stable octet. So that they do not have any tendency to combine with other elements which makes the valency of xenon zero. Because valency is all about lose, gain, or share of electrons.

We can also find the valency of xenon with the help of a periodic table. As xenon belongs to group 8A which are groups of noble gases having valency zero.