Final answer:
The molecular formula for a neutral compound formed by the reaction of potassium and chlorine is KCl, representing an ionic bond between potassium ions and chloride anions.
Step-by-step explanation:
When potassium reacts with chlorine to form a neutral compound, the resulting molecular formula is KCl. This formula indicates a one-to-one ratio of potassium ions (K+) to chloride ions (Cl-), reflecting the transfer of one electron from potassium to chlorine to achieve stable electron configurations. This transfer forms an ionic bond between the two atoms, creating a salt composed of potassium cations and chloride anions. Potassium chloride is an example of such an ionic compound.