# Where does the 5s sublevel go?

1. ### Dgonzo15

14
The first four subshells have one s sublevel, then s and p, then s, p, and d, and then s, p, d, and f, respectively. Where does the 5s go? Does it go in the fifth atomic shell? If that's the case, where does the 7th s sublevel go? From my understanding, the 7th s sublevel would go in the 7th shell (n=7), but what would happen with the f and d sublevels? Looking at the periodic table, there are only 4 d sublevels and 2 f sublevels, so by the time we reach the 5th atomic shell, we use up the last f sublevel and at the 6th we use the last d sublevel, so will the 7th shell be composed only of s and p sublevels?!

### Staff: Mentor

Do you know the Aufbau principle? It is not that there is no "7f", it exists, it just happens there are no known elements where it is filled in the ground state.