How Many Valence Electrons Does Helium (He) Have?
Helium is the second element in the periodic table and the first element in Group -18. The symbol for the helium element is ‘He’. The valence electrons are the total number of electrons in the last orbit(shell).
The total number of electrons in the last shell after the electron configuration of helium is called the valence electrons of helium. The last shell of helium has two electrons. Therefore, the valence electrons of helium are two.
Helium does not participate in chemical reactions and bond formation. This article discusses in detail how to easily calculate the number of valence electrons in helium. Hopefully, after reading this article you will know in detail about this.
How do you calculate the number of valence electrons in a helium atom?
The valence electrons have to be determined by following a few steps. The electron configuration is one of them. It is not possible to determine the valence electron without electron configuration.
Knowing the electron configuration in the right way, it is very easy to determine the valence electrons of all the elements.
However, valence electrons can be easily identified by arranging electrons according to the Bohr principle. Now we will learn how to determine the valence electrons of helium.
Step-1: Determining the total number of electrons in helium
First you need to know the total number of electrons in the helium atom. For this, the atomic number of helium elements must be known. The atomic number is the number of protons in that element.
And electrons equal to protons are in that atom. The periodic table shows that the atomic number of helium is two. That is, the total number of electrons in the helium atom is two.
Step-2: Need to do electron configuration of helium
Step 2 is very important. In this step, the electrons of helium have to be arranged. We know that helium atoms have a total of two electrons. These two electrons enter the first shell.
Step-3: Determine the valence shell and calculate the total electrons
The third step is to calculate the total number of electrons in the last shell. And we already know that the total number of electrons in the last orbit is the valence electron.
The electron configuration shows that the first shell of helium is the last shell and there are two electrons in total. Therefore, the valence electrons of helium are two.
What is the valency of helium?
The ability of an atom of an element to combine with another atom during the formation of a compound is called valency. Helium is an inert element. Therefore, the valency of helium is zero.
Reasons for placing helium in group 18 of the periodic table
The electron configuration of helium shows that the number of electrons in the last orbit of the helium atom is two. We know that the number of electrons in the last orbit of an element is the number of groups in that element.
Accordingly, the group of helium is two but helium is an inert element. All inert elements are placed in group number 18 in the periodic table. Therefore, helium is placed in group 18 instead of group 2.
Why is helium an inert gas?
The elements in group 18 of the periodic table are inert gases. The inert gases of Group-18 are helium, neon(Ne), argon(Ar), krypton(Kr), xenon(Xe), and radon(Rn).
We know that the element in group-18 is helium. The electron configuration of helium shows that the orbit at the end of helium is filled with electrons.
Helium does not want to exchange or share any electrons because the last orbit of helium is full of electrons.
And helium does not form any compounds because it does not share any electrons. They do not participate in chemical bonding and chemical reactions.
For this, they are called inert elements. The inert elements are in the form of gases at normal temperatures. For this, inert elements are called inert gases.