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Author Question: Tritium has a half-life of 12.3 years. How many years will elapse when the radioactivity of a ... (Read 95 times)

olgavictoria

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on: Jul 28, 2018
Tritium has a half-life of 12.3 years. How many years will elapse when the radioactivity of a tritium sample diminishes to 30 of its original value?
 a. 29 years
  c. 86 years
  b. 21 years
  d. 57 years

Question 2

A pure sample of 226Ra contains 3.0  1014 atoms of the isotope. If the half-life of 226Ra = 1.6  103 years, what is the decay rate of this sample? (1 Ci = 3.7  1010 decays/s)
 a. 2.7  10-12 Ci
  c. 3.4  10-10 Ci
  b. 11  10-8 Ci
  d. 7.4  10-8 Ci


ecabral0

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Reply #1 on: Jul 28, 2018
Answer to Question 1

B

Answer to Question 2

B


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