This bundle of PowerPoints covers R2.1 How much? The amount of chemical change for IBDP Chemistry (first examination 2025), including equations, stoichiometry, yield and atom economy. It provides a complete, structured sequence of lessons to build strong quantitative chemistry skills from foundational concepts to exam-level problem solving. The amount of chemical change refers to how chemists measure and calculate the quantities of reactants and products involved in reactions. Using balanced che