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Home Q & A Board Science-Related Homework Help Chemistry (Moderator: Laser_3)
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susu susu
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10 months ago
Rubidium–87 decays by beta decay with a half-life of 4.9 × 1010 yr.  How many 87Rb atoms are in a moon rock sample that has a rubidium decay rate of 3,500 disintegrations per hour?

▸ 9.0 × 1016 atoms

▸ 4.3 × 10–4 atoms

▸ 2.2 × 1018 atoms

▸ 2.5 × 1014 atoms

▸ 1.7 × 1014 atoms
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Chemistry

Chemistry


Edition: 11th
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nnennennenne
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10 months ago
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susu Author
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10 months ago
Thanks for your help!!
Morgan-C
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Yesterday
You make an excellent tutor!
MLynneMcMillan
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2 hours ago
Good timing, thanks!
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