Industrial food preservation and medical sterilization facilities often utilize Cobalt-60 (2760Co^{60}_{27}\text{Co}2760Co) to emit high-energy gamma radiation. The decay sequence begins with 2760Co^{60}_{27}\text{Co}2760Co decaying to an excited state of a nickel isotope, 2860Ni∗^{60}_{28}\text{Ni}^*2860Ni∗, via the emission of a single ionizing particle XXX.
Which option correctly identifies particle X X\,X and describes how the proton number (ZZZ) and neutron number (NNN) of the parent nucleus change during this initial step?
Particle XXX is a β−\beta^-β− particle; ZZZ increases by 111; NNN decreases by 111.
Particle XXX is a β−\beta^-β− particle; ZZZ decreases by 111; NNN increases by 111.
Particle XXX is a β+\beta^+β+ particle; ZZZ decreases by 111; NNN increases by 111.
Particle XXX is a β+\beta^+β+ particle; ZZZ increases by 111; NNN decreases by 111.
90 exam-style questions on OCR A A Level Physics Nuclear and particle physics, covering The nuclear atom, Fundamental particles, Radioactivity, and Nuclear fission and fusion. Each one has a worked solution and a mark scheme showing where the marks go.