Answer :
To determine the parent nuclide of an unstable isotope that decays to produce silicon-31 and a beta particle, we need to consider the process of beta decay. In beta decay, a neutron within the nucleus is converted into a proton, an electron (beta particle), and an antineutrino.
1. Start with silicon-31 (Si-31), which is the product of the decay.
2. Identify the element that has one less proton than silicon-31, which would be phosphorus-31 (P-31). Phosphorus-31 has one less proton than silicon-31.
3. Determine the parent nuclide by looking for an isotope of phosphorus that undergoes beta decay to produce silicon-31.
4. The parent nuclide in this case is phosphorus-31 (P-31) because it undergoes beta decay by converting a neutron into a proton, resulting in the formation of silicon-31 and a beta particle.
Therefore, the parent nuclide that decays to produce silicon-31 and a beta particle is phosphorus-31 (P-31).
