Question

What's the electron configuration for Oganesson? Atomic number-118

Answer 1

`[Rn] 7s^2 5f^14 6d^10 7p^6`

Explanation:

For oganesson, we should probably use noble gas notation (to indicate that it has the same electron configuration as that noble gas to a certain point) because it would get too long otherwise.

The closest noble gas to oganesson is radon. So, make that the first part of the answer:
`[Rn]`

Then, read the periodic table from left to right, beginning from radon.

As you see, to get to oganesson, we go through:

1. The complete `7s` orbital. The maximum number of electrons in the `s` orbital is `2`. It's full, so oganesson has `2` electrons in the `7s` orbital.
2. The complete `5f` orbital (for the `f` orbitals, subtract `2` from the period number to get the energy level. So, for us, it would be `7-2=5`.) The maximum number of electrons in the `f` orbital series is `14`. It's full, so oganesson has `14` electrons in the `5f` orbital.
3. The complete `6d` orbital. The maximum number of electrons in the `d` orbital series is `10`. It's full, so oganesson has `10` electrons in the `6d` orbital.
4. The complete `7p` orbital. The maximum number of electrons in the `p` orbital series is `6`. It's full, so oganesson has `6` electrons in the `7p` orbital.

Put that information all together:

`[Rn] 7s^2 5f^14 6d^10 7p^6`