Why is it necessary to convert moles when determining the mass of product during a chemical reaction?

Converting moles is necessary when determining the mass of a product in a chemical reaction because moles provide a standardized way to quantify reactants and products based on their molecular or atomic composition. This conversion allows for accurate calculations using the molar mass of substances, ensuring that the mass of the product can be derived from the stoichiometry of the balanced chemical equation. Without this conversion, it would be difficult to relate the amounts of reactants used to the resulting products produced.