It won't be gone, but only a tiny amount will remain, the rest having been decayed to daughter isotopes, only 1/128th of the original radioactive isotope is remaining, effectively reducing it's radioacitivity quite significantly
It would not be totally be gone, but after so many half lives there would be only trace amounts left, too little to count and obtain meaningful results. Each half life only half of the original isotope is present. So, after 7 half lives, only 1/128 of the original amount present would be left.
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It won't be gone, but only a tiny amount will remain, the rest having been decayed to daughter isotopes, only 1/128th of the original radioactive isotope is remaining, effectively reducing it's radioacitivity quite significantly
It would not be totally be gone, but after so many half lives there would be only trace amounts left, too little to count and obtain meaningful results. Each half life only half of the original isotope is present. So, after 7 half lives, only 1/128 of the original amount present would be left.