How Many Valence Electrons Does Helium Have?

Answer:

Helium has two valence electrons.

Explanation:

Now I am going to show you how many  valence electrons  helium have in just 5 steps.

             Step-1:

First, find the atomic number of helium from periodic table.

From periodic table ,we see that the atomic number of helium is 2.

                 Step-2:

We know that the atomic number of helium is 2.So helium has 2 protons and 2 electrons as the charge of electrons and protons are equal but opposite in nature.The charge of proton is +1 and the charge of electron is -1.

                Step-3:

Now write the electron configuration of helium.

He(2)=1s²

                Step-4:

He(2)=1s²

Now we will find out valence shell of helium from the electronic configuration of  helium.

He(2)=1s²

Valence shell can be found from the highest number of principal quantum number.

You know that principal quantum number is expressed by n.

He(2)=1s²

Here the highest value of n is 1.SoThe valence shell of helium is 1s²

                 Step-5

In this step,we will find out the valence electrons of helium.

We have to know that the electrons of valence shell are called valence electrons.

He(2)=1s²

From the above electron 

configuration 

of helium,we see 

that helium has 2 

valence electrons in its 

valence shell.

So there are two valence electrons of helium.

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