Final answer:
The compound composed of potassium (K) and phosphate (PO4) is K3PO4, or potassium phosphate. Elemental phosphorus and potassium do not typically form a simple binary ionic compound designated as KP.
Step-by-step explanation:
The chemical formula for an ionic compound composed of potassium (K) and phosphorus (P) will depend on the form phosphorus takes in the compound. If we are dealing with the phosphate ion, which has a charge of 3- (PO43-), the ion would need to be balanced with potassium ions, which have a charge of 1+ (K+). Therefore, following the principles of stoichiometry, we would need three potassium ions to balance out the one phosphate ion, giving us the formula K3PO4 for potassium phosphate.
If we refer to elemental phosphorus (P) and potassium (K) without specifying ions, we typically do not combine these two in a simple binary ionic compound. Instead, phosphorus can form various compounds with potassium depending on the reaction conditions, but a common compound isn't simply designated as KP since phosphorus can take on multiple oxidation states and form a variety of compounds.