Which one of the following statements about fission and fusion is false?
◦ Fission occurs among the heaviest isotopes, whereas fusion occurs more readily for light isotopes.
◦ For a fission reaction the mass defect (Δm) is negative, whereas for fusion Δm is positive.
◦ In order for fusion reactions to occur, temperatures must be in the millions of degrees.
◦ The fission of Pu-239 atoms produces a great number of isotopes of a large number of elements.
◦ Neutron-induced fission processes can occur at room temperature, rather than at millions of degrees.