Moderate

In a radioactive series, 23892U changes to 20682Pb through n1 α-decay processes and n2 β-decay processes.

Correct answer: B. n1 = 8, n2 = 6

  • A. n1 = 8, n2 = 8
  • B. n1 = 8, n2 = 6
  • C. n1 = 6, n2 = 6
  • D. n1 = 6, n2 = 8

Explanation

The radioactive decay series you've described involves the transformation of uranium-238 (^238U) into lead-206 (^206Pb) through a sequence of alpha (α) and beta (β) decay processes. This process is often referred to as the "Uranium-238 decay series" or the "Uranium-238 to Lead-206 decay chain." Here's a breakdown of the steps involved Alpha Decay (α-decay): Uranium-238 undergoes a series of alpha decay processes, where it emits an alpha particle (two protons and two neutrons) from its nucleus. This leads to the formation of a new nucleus. The atomic number of the daughter nucleus decreases by 2, and the mass number decreases by 4. This continues through several decay steps until the atomic number reaches that of lead-82 (^206Pb). Beta Decay (β-decay): Once uranium-238 has transformed into thorium-234 (^234Th), further decay processes involve beta decay. In beta-minus decay (β-), a neutron in the nucleus is transformed into a proton, an electron (beta-minus particle), and an antineutrino. The electron is emitted, and the atomic number of the nucleus increases by 1. The entire decay series involves multiple steps, and it's essential to consider each decay step separately. The final product is lead-206 (^206Pb), which is a stable isotope. This decay series is an example of a natural radioactive process that occurs in certain heavy elements, ultimately leading to the formation of stable daughter isotopes. It's also significant in the context of radiometric dating, where the ratio of parent isotopes (like uranium-238) to daughter isotopes (like lead-206) is used to estimate the age of rocks and minerals.

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About Radioactive Decay

Radioactive decay is the spontaneous transformation of unstable nuclei, described by decay constant, activity, half life and the exponential decay law. Work includes alpha, beta and gamma emissions, decay equations and remaining nuclei, with half life distinguished from the time required for complete decay.

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