The molecular weight of the resulting polymer in a polymerization reaction is directly related to the ratio of monomers used. In general, as the ratio of monomers increases, the molecular weight of the resulting polymer also increases. This is because a higher ratio of monomers provides more opportunities for the monomers to react with each other and form longer polymer chains.However, the relationship between the ratio of monomers and the molecular weight of the resulting polymer is not always linear. The type of polymerization reaction e.g., step-growth polymerization or chain-growth polymerization , the reactivity of the monomers, and the reaction conditions e.g., temperature, pressure, and presence of catalysts or initiators can all influence the molecular weight of the resulting polymer.In step-growth polymerization, the molecular weight of the polymer increases gradually as the reaction proceeds. The ratio of monomers plays a crucial role in determining the final molecular weight of the polymer. A higher ratio of monomers will generally lead to a higher molecular weight polymer, but the reaction must also reach a high conversion rate to achieve this.In chain-growth polymerization, the molecular weight of the polymer is primarily determined by the ratio of monomers to the initiator or catalyst used in the reaction. A higher ratio of monomers to initiator will typically result in a higher molecular weight polymer, as each initiator molecule can initiate the growth of a polymer chain, and a higher monomer-to-initiator ratio allows for longer chains to form.In summary, the molecular weight of the resulting polymer in a polymerization reaction is directly related to the ratio of monomers used, but the relationship can be influenced by the type of polymerization reaction, the reactivity of the monomers, and the reaction conditions.