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A 50g sample of radioactive iodine-131 has a half-life of 8.0 days. After 32 days, how much is left?

User Arjor
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1 Answer

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Answer:

The correct answer is = 3.125 gram.

Step-by-step explanation:

The half-life of iodine-131 is 8 days as given. The half life of is the required time to which a radioactive comond or element left half of its initial life quantity which means that after 8 days, half of the sample (50 gm of iodine 131) would have decayed and half would be left undecayed.

now it is ask that how much amount of iodine 131 left after 32 days, so

32 days = 4 half lives of iodine 131 (8 days * 4 = 32 days)

Thus, after 1st half life = 50/2 = 25gm

2nd half life = 25/2 = 12.5

3rd half life = 12.5/2 = 6.25

and at last fourth half live = 6.25/2 = 3.125

Thus, the correct answer is = 3.125 gram.

User Ben Cavenagh
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