The unstable isotope 234Th decays by ? emission with a half-life of 24.5 days. The initial decay rate of the sample was 9.9 × 1013 Bq. (1 u = 1.6605 × 10-27 kg)
(a) What mass of 234Th was initially present?
(b) What is the decay rate after 68 days?
What will be an ideal response?
Answer: (a) 0.12 g (b) 1.4 × 1013 Bq
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Why does the surface of Triton appear so young?
What will be an ideal response?
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