How many alpha and beta particles are emitted when Uranium 92U238 decays to lead 82Pb206
- 3 alpha particles and 5 beta particles
- 6 alpha particles and 4 beta particles
- 4 alpha particles and 5 beta particles
- 8 alpha particles and 6 beta particles
The Correct Option is D
Solution and Explanation
\(\c{^{238}_{92}U \rightarrow ^{82}_{20}Pb + x^4_2He + y(^{-1}_0e)}\)
\(⇒\) \(206 + 4x = 238 …(1)\)
and \(82 + 2x – y = 92 …(2)\)
\(⇒\)\( x = 8\) and \(y = 6\)
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Concepts Used:
Radioactivity
Radioactivity is a phenomenon observed in certain elements where unstable atomic nuclei spontaneously emit energy and subatomic particles. This process is driven by the desire of the nucleus to achieve a more stable state. It's crucial to understand the three main types of radioactive decay:
Alpha Decay: In alpha decay, a nucleus emits an alpha particle, consisting of two protons and two neutrons.
Beta Decay: Beta decay involves the emission of a beta particle, which can be a positron or an electron, from an unstable nucleus.
Gamma Decay: Gamma decay releases gamma rays, electromagnetic radiation, to achieve a more stable nuclear state.
The emission of these particles and energy is a result of nuclear instability. The rate of decay is characterized by the half-life, the time taken for half of the radioactive material to undergo decay. Radioactivity has diverse applications, from medical treatments and industrial processes to power generation in nuclear reactors.