What is reduced in the reaction Mn + HCl → MnCl2 + H2 ? 1. chlorine in HCl 2. This is not a redox reaction. 3. manganese 4. hydrogen in HCl

Opion 4. The hydrogen in HCl reduce from proton to hydrogen gas (H at ground state)

Explanation:

The reaction is: Mn + HCl → MnCl₂ + H₂

Magnessium changed the oxidation state from 0 to +2

It has increased, so it was oxidized

H changed the oxidation state from +1 to 0

It has decreased, so it was reducted.

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.