A research team is studying three synthetic isotopes. Identical samples are prepared, each containing 1.0×1020 nuclei. Measured half-lives for the isotopes are shown in the table.
Isotope P 1.5h
Isotope Q 15h
Isotope R 150h
(a) Calculate the decay constant for each isotope.
(b) Rank the three isotopes by their initial activity (decays per second), from greatest to least. Explain the reasoning that leads to your ranking.
(c) Determine the number of undecayed nuclei remaining in isotope Q after 30 h.