The term for the position of a molecule in relation to others in a chemical equation is called stoichiometry. This concept refers to the quantitative relationships between the reactants and products of a chemical reaction. Stoichiometry allows chemists to measure how much of each substance is involved in a reaction, ensuring that the law of conservation of mass is upheld. By understanding stoichiometry, chemists can predict the outcomes of reactions, balance equations, and determine reactant requirements for desired product yields.