Question

What is the significance of principal quantum number

Answer 1

Principal quantum number(n) can have values 1,2,3,4 etc.It can give an idea about the size and energy of an orbital. It identifies the energy levels or the shell.n=1,2,3,4 etc
n=1 1st energy level K shell AND SO ON
The number of orbitals allowed in each shell is given by n2. All orbitals of a given value of n constitute a single shell. THUS IT DETERMINES SIZE. !!!

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