For elements in the first three periods of the periodic table (hydrogen - argon), the orbitals can simply be filled up by increasing energy energy level. A difficulty arises when we come to potassium.

There’s another "ah" moment at A-level when you introduce orbitals, and suddenly students understand why there’s a p-block or an s-block. Imagine being at the start of this journey, where you've got ...

The modern periodic table, arranged in rows and columns, was first introduced by Dmitri Mendeleev ... Nuclear scientists refer to this phenomenon as the direct relativistic effect. As a result, the ...

Bismuth is in Group 15 of the periodic table. The s, d and f orbitals are all full, but the p orbitals contain three out of a ...