Question

How many valence electrons does each of the following have:

5.1. S

5.2. C

5.3. Ba

5.4. the halogens

Answer 1

Valence electrons are the electrons present in the last shell of an atom

S has atomic number 16 with electronic configuration 2,8,6. Thus, it has 6 valence electrons

C with atomic number 6 has electronic configuration 2,4. Thus, C has 4 valence electrons

Ba has atomic number 56. Its electronic configuration is 2, 8, 18, 18, 8, 2. So, it has two valence electrons

Halogens belong to group 17 and contain 7 valence electrons.