Radioactivity
Learning Objectives
- Students will be able to identify and describe alpha, beta, and gamma decay
- Students will be able to calculate half-life and decay constants
- Students will be able to write and balance nuclear equations
Core Concepts
- Alpha decay
- Beta decay
- Gamma radiation
- Half-life
Formulas
$$N = N_0 \left(\frac{1}{2}\right)^{t/T_{1/2}}$$
Number of nuclei remaining after time t
$$A = \lambda N$$
Activity (decay rate) equals decay constant times number of nuclei
$$T_{1/2} = \frac{\ln 2}{\lambda}$$
Half-life in terms of decay constant
Units
| Becquerel | Bq |
| Curie | Ci |
Interesting Fact
Beta particles are high-energy electrons emitted when a neutron converts to a proton
Key Scientist
Ernest Rutherford
Studied radioactive decay and identified alpha and beta radiation
Philosophy
Radioactivity reveals spontaneous, unpredictable changes at the atomic level, which challenges the philosophical view of determinism and supports the idea of indeterminism. The random and probabilistic nature of radioactive decay suggests that the universe may not be entirely predictable, contrary to the deterministic worldview.
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