This episode discusses combustion analysis, a method for determining an organic compound's empirical formula by burning it completely and analyzing the products. They explain that all the carbon becomes CO2 and all the hydrogen goes into the H2O produced, which allows for the original masses of these elements to be calculated from the product masses. The episode outlines a four-step process: measure the masses of the products, use stoichiometry to find the masses of carbon and hydrogen, find the mass of oxygen by difference, and finally, convert the masses to moles to determine the empirical formula. This technique is presented as a practical application of stoichiometry to uncover a compound's composition.