The formula of Potassium Bicarbonate is KHCO3.
In the laboratory, baking soda can be prepared by passing excess of carbon dioxide gas through the saturated solution of potassium carbonate. As a result, potassium bicarbonate is formed. Being sparingly soluble in water, it gets precipitated. The precipitate is separated, washed and dried without heating.
K2CO3 + CO2 + H2O -----> 2KHCO3
Here, KHCO3 is a precipitate. It contains one atom of Potassium one atom of Hydrogen one atom of Carbon and three atoms of Oxygen.
Potassium Bicarbonate is also Potassium Hydrogen Carbonate.