The molar mass of KCI03 is 431.82 grams per mole. KCI03 a compound containing one atom of potassium, one atom of chlorine and three atoms of iodine. The molar mass of the similarly written compound KClO3, which is the common chemical potassium chlorate, is 122.54 grams per mole.
The molar mass of either compound can be calculated by adding together the atomic mass of each atom of each element comprising the compound. For example, a compound containing one atom of potassium and one atom of chlorine includes at least the mass of 39.09 grams per mole for a potassium atom and 35.45 grams per mole for a chlorine atom.