Ask Question
19 May, 05:06

Iodine-131 has a half-life of 8 days. How long would it take for the number of unstable nuclei in the sample to be reduced from 1,000 to 125?

+5
Answers (1)
  1. 19 May, 05:10
    0
    After one-half life: 16 mg

    After 2-half lives: 8 mg

    After 3-half lives: 4 mg

    After 4-half lives: 2 mg

    After 5-half lives: 1 mg

    (5 half-lives) x (8 days/half-life) = 40 days

    or doing it the mathematical way: Let z be the number of days to be found:

    1 mg = 32 mg x (1/2) ^ (z / 8 days)

    1/32 = (1/2) ^ (z / 8 days)

    log (1/32) = (z / 8 days) x log (1/2)

    z / 8 days = log (1/32) / log (1/2)

    z = 8 days x log (1/32) / log (1/2) = 40 days
Know the Answer?
Not Sure About the Answer?
Find an answer to your question 👍 “Iodine-131 has a half-life of 8 days. How long would it take for the number of unstable nuclei in the sample to be reduced from 1,000 to ...” in 📗 Chemistry if the answers seem to be not correct or there’s no answer. Try a smart search to find answers to similar questions.
Search for Other Answers