Final answer:
The electronic configuration of potassium (atomic number 19) is [Ar]4s¹, showing that it has one valence electron in the 4s orbital, similar to other alkali metals such as lithium and sodium.
Step-by-step explanation:
The Electronic Configuration of Potassium (Atomic Number 19)
Potassium, with atomic number 19, has 19 electrons. The electronic configuration code for potassium can be written as [Ar]4s¹. When filling the electron shells, we follow the rule that electrons fill the lower energy orbitals first.
In the case of potassium, which follows argon in the periodic table, the electron configuration starts with that of argon (which has 18 electrons) and adds one more electron in the next available energy level, the 4s orbital. Hence, potassium has a similar valence shell configuration to other alkali metals such as lithium and sodium, indicating it has one valence electron in its outermost shell.
This one valence electron makes potassium highly reactive, readily forming the K+ ion when it donates this electron in chemical reactions, resulting in a potassium cation which is essential in biological systems.
The electron configuration of Potassium (atomic number 19) is [Ar]4s1.
As we move across the periodic table, the next electron after the noble gas configuration is added to the 4s subshell rather than the 3d subshell. This is because the 3d orbital is higher in energy than the 4s orbital. Therefore, Potassium has one electron in its 4s subshell.
By adding the electron configuration of Argon ([Ar]), which represents the fully filled 1s, 2s, 2p, 3s, 3p, and 3d subshells, we get the electron configuration of Potassium as [Ar]4s1.