Final answer:
Conservation of baryon number ensures the total atomic mass remains unchanged during nuclear reactions because the sum of baryon numbers remains constant, mirroring the conservation of nucleons. In nuclear decay like beta decay, the transformation of particles respects this conservation, as illustrated in the decay of Cobalt-60 with a constant nucleon count of 60. So, the correct option is c).
Step-by-step explanation:
The conservation of baryon number is a fundamental principle in physics that ensures the total atomic mass (or the total number of nucleons) remains unchanged during nuclear decay and reactions. In these processes, every particle is assigned a baryon number: +1 for baryons, -1 for antibaryons, and 0 for all other particles. During nuclear decay, such as beta decay, a neutron turns into a proton while emitting a beta particle, which maintains the same total number of nucleons. The conservation of the total baryon number is a more general rule observed from nuclear physics, where it was initially recognized that the total number of nucleons is always conserved in nuclear reactions.
For example, in the decay of Cobalt-60, there are 60 nucleons before and after the decay. This is because the sum of the baryon numbers before and after the reaction remains constant, thus ensuring the conservation of total atomic mass. When considering the different options provided in the question, the one that is related to the conservation of atomic mass is through the creation of antimatter (option c), although the wording 'creation' might be misleading as it suggests the fabrication of new particles rather than transformation or decay procedures that conserve baryon number and thus atomic mass.