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valentina_108 [34]
3 years ago
13

I WILL GIVE BRAINLIEST

Chemistry
1 answer:
inn [45]3 years ago
3 0

Answer:

5.75 g.

Explanation:

  • It is known that the decay of isotopes of Pb-189 obeys first order kinetics.
  • Also, it is clear that in first order decay the half-life time is independent of the initial concentration.
  • The half life time of Pb-189 decay = 20 days.
  • Thus, 60 hours represent (60/20) 3 half-lives.

<em>∴ 46 g →(first half-life) 23 g →(second half-life) 11.5 g →(third half-life) 5.75 g.</em>

<em></em>

  • <em>So, The amount remained is 5.75 g after 3 half-lives (60 days).</em>
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