Question

With what quantum number does every period in periodic table begin?

Answer 1

If the period number is 1 the quantum no is 1, and so every period number represent its respective quantum number 

Answer 2

The three quantum numbers (n, l, and m) that describe an orbital are The principal quantum number (n) cannot be zero. The allowed values of n are therefore 1, 2, 3, 4 , and so on.