Question

What's the electronic configuration for an atom that has 33 electrons?

Answer 1

The (neutral) atom that has 33 electrons is called Arsenic (`As`), and its electron configuration can be written like this:

`"As":1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)4s^(2)3d^(10)4p^(3)`

Another way to write the electron configuration for `As` is to use the noble gas shorthand notation. This is done by determining the noble that comes before `As` in the periodic table, which is Argon (`Ar`).

The electron configuration for `Ar` is

`"Ar": 1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)`

Using this to replace the matching portion of `As`' configuration will give

`"As": ["Ar"]4s^(2)3d^(10)4p^(3)`