How many valence electrons are in an atom with the electron configuration in example A?

Example A: 1s22s22p63s23p4

6

4

2

18

The answer is 6 valence electrons

6.

Explanation:

Valence electron may be defined as the electrons present in the outermost shell. The valence electron has the ability to lose or gain the other electron and also determines the chemical property of the element.

The outermost electrons can be calculated by looking at the outermost shell. In the given example 1s22s22p63s23p4, the number of valence electrons are 6 (the sum of electron present in the 3s and 3p orbitals.

Thus, the correct answer is option (1).