How long would a single molecule of a radioactive element last?
If the half-life of U-235 reduces its mass by half, and the resulting mass is also reduced into half by another half-life term, then a given mass would last indefinitely, because a half would always remain. In other words, some molecule of that radioactive mass would last longer than the rest of the molecules. Isn't the lifetime of a single molecule of that radioactive a constant? Is the concept of "half-life" valid?
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