For example, when Cao (B) reacts with Co2 (A), CaCO3 (C) is formed. The reaction takes place when the CO2 reaches the global Cao surface. As a result of the reaction, CaCO3 is formed around Cao and over time, the product layer thickens while the reactant Cao gets smaller. One of the models that we can explain such systems is the shrinking core model. Write expressions showing the concentration distribution of carbon dioxide and how the Cao core radius changes over time. Try to solve the problem in detail.