Question

What is the valence electron configuration for potassium?

Answer 1

We know that the combining capacity of an atom is known as its valency. The number of bonds that an atom can form as part of a compound is expressed by the valency of the element. Valency is a measure of the ability of an atom to bond with other atoms.

Complete answer:
As we know that the valency of an element is determined by octet rule. Other element’s reactivity depends upon their ability to attain the noble gas configuration. If the outermost shell has eight electrons, then the element is said to have a complete octet. By gaining, sharing and losing the electrons the atoms complete their outermost orbital and make an octet.
The reactivity of an atom is described by the total number of electrons lost, gained or shared to complete its octet and it also determines the valency of the atom. The outermost shell of any element is the shell of Valence. Atoms in individual elements have various electrical properties, based on the atomic number of each element. The electrical arrangement refers to the distribution of electrons in various shells of energy at each atom. The number of electrons in the outermost shell of a given atom determines either its reactivity, or a propensity to form chemical bonds with other atoms.
This outermost shell is known as the valence shell, and the electrons trapped inside are known as valence electrons. Potassium is an element present in the very first group of the periodic table. It decides the valency which is the most important number as it provides ground for the most of the properties of the elements. We know that the atomic number of Potassium is $19.$ Its electronic configuration will be $2,8,8,1.$ So this implies that the outermost shell is having one electron so this implies that valence of Potassium will be $1.$

Note:
Remember that the valence is the combining power of an element. Elements in the same group of the periodic table have the same valence. The valence of an element is related to how many electrons are in the outer shell.