Non-valence electrons: 1s22s22p6. Therefore, we write the electron configuration for Na: 1s22s22p63s1. What is the highest principal quantum number that you see in sodium's electron configuration? It's n = 3, so all electrons with n = 3 are valence electrons, and all electrons with n < 3 are non-valence electrons.
They turn litmus paper blue
Answer:
Actinides
Explanation:
They are defined as "any of the series of fifteen metallic elements from actinium (atomic number 89) to lawrencium (atomic number 103) in the periodic table. They are all radioactive, the heavier members being extremely unstable and not of natural occurrence"