Back عدد كم رئيسي Arabic Baş kvant ədədi Azerbaijani Главно квантово число Bulgarian মুখ্য কোয়ান্টাম সংখ্যা Bengali/Bangla Nombre quàntic principal Catalan Hlavní kvantové číslo Czech Κύριος κβαντικός αριθμός Greek Ĉefa kvantuma nombro Esperanto Número cuántico principal Spanish Zenbaki kuantiko nagusi Basque
In quantum mechanics, the principal quantum number (symbolized n) is one of four quantum numbers assigned to each electron in an atom to describe that electron's state. Its values are natural numbers (from one) making it a discrete variable.
Apart from the principal quantum number, the other quantum numbers for bound electrons are the azimuthal quantum number ℓ, the magnetic quantum number ml, and the spin quantum number s.