Question

How many valence electrons does oxygen have?

Answer 1

Hint To find the number of valence electrons in oxygen atom , you should first know that how many electrons are present in oxygen and then, calculate the total number of electrons present in the s, p and d-orbitals to get the valence electrons. Now you can easily answer the statement.

Complete step by step answer:
Oxygen is a non-metal and a gas which comes under the category of chalcogens and belongs to the p-block elements of the periodic table.
It lies in the 16th group and 2nd period of the periodic table.
It has an atomic number as 8 and a mass number as 16. It has the electronic configuration as: $1s^{2}2s^{2}2p^4$.
Now considering the statement as;
The number of electrons present in an atom is always equal to the atomic number of that very element.
And The electrons which are present in the outermost valence shell of an atom are called the valence electrons.
From the electronic configuration of the oxygen atom, we come to know that the number of electrons present in the outermost shell i.e., 2rd shell is 6 electrons.

Thus, the total number of valence electrons present in an oxygen atom is six.

Note: Oxygen being a chalcogen has six electrons in its outermost shell and requires only two electrons to complete its octet. So, oxygen has a strong tendency to gain two electrons from the other electron donating species and thus, it acts as a strong Lewis acid.