Nuclear Reactions
A nuclear reaction occurs between nuclides and fundamental particles to produce different nuclides. This is different from a chemical reaction where electrons are shared/transfered between elements and compounds are changed. Nuclear reactions release significantly more enegy and result in a change in mass between intial reactants and products.
When a nuclide is unstable (radioactive) is can decay by various nuclear processes to a lower (stable) energy state. Some examples are shown below.
| Decay Mode | General Equation | Description |
| Alpha | \( {^A_Z}X \rightarrow {^{A-4}_{Z-2}}X^{'} + {^4_2}\alpha \) | Heavy atoms release a He particle. |
| Beta (-) | \( {^A_Z}X \rightarrow {^A_{Z+1}}X^{'} + \ce{^0_-1\beta} \) | A neutron is converted into a proton and an electron is released. |
| Beta (+) | \( {^A_Z}X \rightarrow {^A_{Z-1}}X^{'} + \ce{^0_+1\beta} \) | A proton is converted into a neutron and a positron is released. |
| Proton Emission | \( {^A_Z}X \rightarrow {^{A-1}_{Z-1}}X^{'} + \ce{^1_1p} \) | A proton is ejected. |
| Neutron Emission | \( {^A_Z}X \rightarrow {^{A-1}_{Z}X} + \ce{^1_0n} \) | A neutron is ejected. |
| Internal Conversion | \( {^A_Z}X \rightarrow {^A_ZX} + \ce{^0_-1e} \) | Electron is ejected. |
| Gamma | \( {^A_Z}X \rightarrow {^A_ZX} + \gamma \) | Energy is released but the nuclide does not change (isomer). |
| Spontaneous Fission | \( X \rightarrow Y + Z \; ... \) | A nuclide splits into two or more smaller nuclie and other particles. |
A radioactive nuclide may have different decay modes. It may also decay to another unstable daughter nuclide which subsequently decays. A decay scheme is a visual representation of the decay modes for a nuclide.
The decay scheme for Co-60 is shown below. What is the daughter nuclide and energy of the missing gamma decay?
Other nuclear reactions invovle the interaction between nuclides or particles. Some examples are shown below.
| Reaction | Equation | Description |
| Radiative Capture | \( (n,\gamma) \) | Absorption of a neutron and release of a gamma. |
| Particle Emission | \( (n,\alpha), (n,p), (n,2n) \) | Absorption of a neutron and release of a particle. |
| Induced Fission | \( (n,f) \) | Absorption of a neutron, splitting into multiple nuclides and particles. |
| Fusion | \( A + B + \; ... = C + \; ... \) | Combination of multiple nuclides and particles. |
What is the result of the following equation: \( ^{10}B(n,\alpha) \)