Answer: Option (3) is the correct answer.
Explanation:
In a Lewis electron-dot diagram of an atom shows bonding between different atoms or in a molecule. It also represents lone pairs of electrons that are present over a molecule.
In this diagram, electrons in the outermost shell are represented with the help of dots around the symbol of atom or molecule.
For example, valency of nitrogen is 5 this means nitrogen has 5 electrons in its outermost shell.
Thus, we can conclude that the number of valence electrons in the atom are represented by the dots in a Lewis electron-dot diagram of an atom of an element in Period 2 of the Periodic Table.
