Formulas of synthetic polymers I have a question regarding synthetics. $\ce{(C8H8)}_n$ is the formula for polystyrene. What exactly does the $n$ stand for? 

Thanks
n is the number of molecular units in a chain, also called the degree of polymerization. This varies based on the molecular weight of the polymer. The molecular weight is the degree of polymerization times the molecular weight of a monomer.