Final answer:
The ratio of the effusion rates of 235UF6 and 238UF6 can be calculated using Graham's law. 235UF6 effuses approximately 1.014 times faster than 238UF6.
Step-by-step explanation:
The ratio of the effusion rates of 235UF6 and 238UF6 can be calculated using Graham's law. Graham's law states that the ratio of the effusion rates of two gases is equal to the square root of the ratio of their molar masses. In this case, the molar mass of 235UF6 is 349.0 g/mol and the molar mass of 238UF6 is 352.0 g/mol.
Ratio of effusion rates = sqrt(352.0 / 349.0) = 1.014 (approximately)
Therefore, 235UF6 effuses approximately 1.014 times faster than 238UF6.