How many neutrons are present in an atom of chlorine-37? a. 17 b. 18 c. 19 d. 20

if two electrons have the same n, the same ℓ, and the same ml, then they are in the same orbital. the pauli exclusion principle states that no two identical fermions (a fancy word for electrons and other subatomic particles like electrons) may occupy the same quantum state in an atom simultaneously.

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.