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A research person made 160 mg of radioactive sodium and found that there was only 20 mg left 45 hours later. what is the half life of radioactive sodium?
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Notice that 20 mg = mg, and = .
It means that 45 hours comprise of 3 half-life periods.
So, one half-life period is one third of 45 hours, i.e. 15 hours.
ANSWER. Half-life is 15 hours.
Solved and explained.
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On radioactive decay, see the lesson
- Radioactive decay problems
in this site.
You will find many similar (and different) solved problems there.
Use this lesson as your handbook, textbook, guide, tutorials, and (free of charge) home teacher.
Learn the subject from there once and for all.
Also, you have this free of charge online textbook in ALGEBRA-I in this site
- ALGEBRA-I - YOUR ONLINE TEXTBOOK.
The referred lesson is the part of this online textbook under the topic "Logarithms".
Save the link to this online textbook together with its description
Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson
to your archive and use it when it is needed.