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Course: High school chemistry > Unit 9

Lesson 1: Radioactive decay
Science
High school chemistry
Nuclear chemistry
Radioactive decay
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Apply: alpha decay

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Problem

The isotope plutonium-238 is used on some space probes to generate thermal energy. It decays by the emission of an alpha particle.
Artist's concept of Cassini during the Saturn Orbit Insertion maneuver.
Artist's concept of Cassini in orbit
After an alpha particle is emitted, what is the atomic number of Pu-238’s daughter isotope?
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi