Final answer:
The number of bromine molecules in the flask is approximately 2.595 x 10^23 molecules.
Step-by-step explanation:
In order to determine the number of bromine molecules present in the flask, we can use Avogadro's number which relates the number of particles in a mole of substance. Avogadro's number is approximately 6.022 × 1023 particles per mole.
Given that the flask contains 0.430 mol of bromine, we can calculate the number of bromine molecules as follows:
Number of bromine molecules = (0.430 mol) × (6.022 × 1023 molecules/mol) = 2.595 × 1023 molecules