KCl is a neutral SALT. It is ionic and is usually called a compound, not a molecule.

(Molecule refers to the smallest unit of a covalent bond containing compound. The atoms in KCl undergo ionic bonding.)

Potassium and all the other group IA elementas (lithium, sodium, cesium, rubidium, and francium) almost always have an oxidation state of +1. Chlorine has an oxidation state of -1 unless it is bonded to oxygen or fluorine. So it is a good bet that the potassium has a +1 charge. In solution, represent the potassium as K+ to indicate this charge, though in a compound such as KCl, the charges are not shown since they are balanced.

A stable compound usually has an oxidation number of zero.This is because they must have exchanged and balanced their oxidation numbers which is also called the combining power of their ions.Hence Potassium (K)Chloride(Cl) KCl has oxidation number of zero.

K has +1 combining power and Cl has -1 combining power ,since the addition of the two combining power +1 and -1 equals zero,the compound is a stable one .

Therefore, K ⁺¹ + Cl^-1   ----------> KCl ^+1-1  (KCl)⁰

Thus the charge on K in KCl  is +1

Since KCl is a neutral molecule, the sum of the oxidation states of the atoms equals zero.

We know that potassium (K) has an oxidation of +1 since it is a group 1 element.

So,   K⁺¹Cl^-1  ===> KCl⁰ OR KCl.

Thus, the charge on potassium (K) in KCl is +1.