#7) Normal levels of the uranium-235 isotope are about 0.72%, with the majority being uranium-238. Round the level up to 1% (in the favor of uranium-238), to one atom of uranium-235 and 99 atoms of uranium 238. Use the
simulation to discover if naturally-derived uranium can start a chain reaction (and therefore be useful in either
nuclear weapons or nuclear power plants): Is naturally derived uranium able to start a chain reaction, or must the
sample be "enriched”?

Two nitro no2 groups are chemically bonded to a patch of surface. they can't move to another location on the surface, but they can rotate (see sketch at right). it turns out that the amount of rotational kinetic energy each no2 group can have is required to be a multiple of ε, where =ε×1.010−24 j. in other words, each no2 group could have ε of rotational kinetic energy, or 2ε, or 3ε, and so forth — but it cannot have just any old amount of rotational kinetic energy. suppose the total rotational kinetic energy in this system is initially known to be 32ε. then, some heat is removed from the system, and the total rotational kinetic energy falls to 18ε. calculate the change in entropy. round your answer to 3 significant digits, and be sure it has the correct unit symbol.