3 rules that define how electrons<span> can be </span>arranged<span> in an </span>atom's<span> orbital. All orbitals related to an energy level are of equal energy. Single </span>electrons<span> with the same spin must occupy each equal-energy orbital before additional </span>electrons<span> with opposite spins can occupy the same orbitals.</span>
The three correct rules or principles are the Aufbau
Principle, Hund’s Rule, and the Pauli Exclusion Principle. Aufbau’s Principle
states that each electron orbits the lowest energy orbital. It also states that
all orbitals related to an energy level are of equal energy. Hund’s Rule states
that single electrons with the same spin must occupy each equal-energy orbital
before additional electrons with opposite spins can occupy the same orbitals.
And finally, the Pauli Exclusion Principle states that a maximum of two electrons
may occupy a single orbital, but only if the electrons have opposite spins.
Hope this helps.
Each molecule of O2 is made up of 2 oxygen atoms. So 1 mole of O2 molecules is made up of 2 moles of oxygen atoms. Therefore 1 mole of oxygen gas contains 2 moles of oxygen atoms. And 0.4 moles of oxygen gas contains 0.8 moles of oxygen atoms.
