How would you write the formula for potassium metal?

To write the formula for potassium metal, you need to understand a few basic concepts about elements and their symbols in chemistry.

Element Symbol: Each chemical element is represented by a one- or two-letter symbol. For potassium, the symbol is K. This symbol comes from the Latin name for potassium, kalium.

Metallic Form: When referring to potassium metal, it is simply the elemental form of potassium, which is a soft, silvery-white metal that is highly reactive.

Elemental State: The elemental state of metals is usually represented by their symbol alone, without any additional notation. Unlike compounds that consist of two or more different elements, elemental potassium does not combine with any other elements when expressed in its pure metallic form.

Conclusion:
Therefore, the formula for potassium metal is simply K.