The atoms of an element can come in different forms, depending on the number of neutrons in the nucleus. These different forms are called isotopes of the element. The two most common isotopes of uranium are uranium-235 (143 neutrons) and uranium-238 (146 neutrons), having masses of \(3.90 \times 10^{-25} \mathrm{~kg}\) and \(3.95 \times 10^{-25} \mathrm{~kg}\), respectively. In a sample of uranium gas, these isotopes have slightly different root-mean-square speeds, and this difference can be used to separate the isotopes for use in nuclear reactors or nuclear weapons. When both gases are at the same temperature, what is the percent difference in the root-mean-square speeds of the atoms of each isotope? Which isotope has the greater root-mean-square speed?