numbers in electron configuration

[Funmi Baruwa]

When writing electron configurations, what does the number in front of the configuration symbolize. for example in 1s^2 2s^2, what do the 1 and the 2 symbolize?

[Faaizah Arshad 1H]

The number tells you what shell the electron is in. It is the principal quantum number (n).

[JaesalSoma1E]

The 1 and 2 are the principal quantum number, n, which tells you what shell the electron is in.

[Kelly Tran 1J]

The number in front of the configuration (in your case 1 and 2) is the principal quantum number(n), which is called the shell and tells you the energy and size of the electron. The larger the value of n, the larger the electron, and the more energy it has.

[OwenSumter_2F]

And then the second number, the subscript, is the amount of orbitals in each subshell.

[KhanTran3K]

Hey!
Just to add on, as the value of "n" increases, or the principal quantum number, since it is at a higher energy level, this allows for more orbitals (s, p, d, f), which are represented by the letter l. Also, the number in the exponent spot represents the number of electrons in the orbital at that energy level.
Hope that helps! :)