The table below describes four nuclides.
| cobalt-60 | nickel-60 | cobalt-57 | iron-56 | |
|---|---|---|---|---|
| nuclide notation | 2760Co^{60}_{27}\text{Co}2760Co | 2860Ni^{60}_{28}\text{Ni}2860Ni | 2757Co^{57}_{27}\text{Co}2757Co | 2656Fe^{56}_{26}\text{Fe}2656Fe |
(i) Determine which two nuclides have the same number of nucleons.
(ii) Determine which nuclide has the largest number of neutrons.
Cobalt-60 has a half-life of 5.3 years. A sample of radioactive material contains 80 mg of cobalt-60. Calculate the mass of cobalt-60 remaining in the sample after 15.9 years.
170 exam-style questions on CIE IGCSE Physics 5.1.2a Composition of the nucleus and isotopes. Each one has a worked solution and a mark scheme showing where the marks go.