# How many valence electrons are in a chlorine atom

By John

Solution

Chlorine has an atomic number 17. Atomic number is the number of protons present in the nucleus of an atom. All the atoms of an element have same atomic number. In every stable atom the number of electrons is equal to the number of protons. Therefore, the number of electrons is equal to the number of protons in an chlorine atom. This means, that the number of electrons present in an chlorine atom is 17.
The electronic configuration of chlorine atom is:-
E.C – K,L,M
2,8,7
Where k,l,m are the shells/orbits/ energy levels of an chlorine atom.
Valence electrons are the number of electrons present in the outermost shell of an atom. Now, the last shell of chlorine atom has 7 electrons in it. Therefore, there are 7 valence electrons present in an chlorine atom.Chlorine has an atomic number 17. Atomic number is the number of protons present in the nucleus of an atom. All the atoms of an element have same atomic number. In every stable atom the number of electrons is equal to the number of protons. Therefore, the number of electrons is equal to the number of protons in an chlorine atom. This means, that the number of electrons present in an chlorine atom is 17.
The electronic configuration of chlorine atom is:-
E.C – K,L,M
2,8,7
Where k,l,m are the shells/orbits/ energy levels of an chlorine atom.
Valence electrons are the number of electrons present in the outermost shell of an atom. Now, the last shell of chlorine atom has 7 electrons in it. Therefore, there are 7 valence electrons present in an chlorine atom.