Chemistry / Unit 5 Chem 0822 short lesson, about 20 seconds
The Principal Quantum Number, n
Captions available
The idea
The principal quantum number, n, is a positive integer setting an orbital's shell, governing electron energy and distance from the nucleus.
In practice
An electron in the n = 1 shell sits closer to the nucleus and at lower energy than one in n = 3.
Where people slip
A higher n marks a higher-energy, more distant shell — it says nothing about orbital shape.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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