Final answer:
The polymerization of propene to form polypropylene has a 100% atom economy as all the atoms of propene are utilized in the polymer with no by-products.
Step-by-step explanation:
The atom economy of a reaction is a measure of the efficiency with which atoms from the reactants are incorporated into the desired products. In the case of the polymerization of propene to form polypropylene, the reaction has a 100% atom economy because all atoms of the monomer propene are converted into the polymer without any loss of material. Since there are no by-products in this chain-growth polymerization process, the atom economy is considered perfect. Polypropylene is a versatile material used in various applications, including plastic utensils, containers, and many household products.