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Why does potassium usually form a positive one ion?
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![A periodic table element box for potassium shows atomic number 19, symbol K, atomic weight 39.0983, electron configuration [Ar]4s1, and name potassium. Icons indicate it is an alkali metal, solid at room temperature, body-centered cubic crystal structure, and has strongly basic higher-valence oxides. A key explains the symbols for alkali metals, solid state, body-centered cubic structure, and strong basicity.](https://cdn.britannica.com/81/22381-050-E3372C94/properties-Potassium.jpg)
potassium
Properties of potassium.
Potassium (K) typically forms a positive one (+1) ion because it has a single valence electron in its outermost 4s orbital. This electron is weakly bound and easily removed. By losing this single electron, the potassium atom achieves a stable electron configuration similar to that of a noble gas, consistent with the octet rule.1234
As an alkali metal, potassium is highly reactive and readily forms these singly charged positive cations when reacting with nonmetals. This process is driven by the relatively low ionization energy required to remove that outermost electron.32