Final answer:
The exact chemical reaction producing 9.81 x 10²⁵ CO₂ molecules is not provided; however, examples include the combustion of propane and reaction of calcium carbonate with hydrochloric acid.
Step-by-step explanation:
The question refers to a chemical reaction that results in the production of 9.81 x 10²⁵ CO₂ molecules. Without a specific reaction given, we cannot determine the exact reaction that would produce this number of molecules. However, to exemplify how one might calculate the number of CO₂ molecules produced in a reaction, let's consider the combustion of propane. The balanced chemical equation is C₃H₈ + 5 O₂ → 3 CO₂ + 4 H₂O. Here, combusting one mole of propane (C₃H₈) results in three moles of CO₂. Similarly, in the reaction of calcium carbonate with hydrochloric acid (CaCO₃ + 2 HCl → CaCl₂ + CO₂ + H₂O), one mole of CaCO₃ produces one mole of CO₂.