The half-life of a radioactive isotope is 8 years. If a sample initially has 640 grams, how much remains after 32 years?

Thu, 16 Apr 2026 21:41:44 +0000

**The Half-Life of a Radioactive Isotope: How 640 Grams Decay Over 32 Years** Curious why a small fragment of radioactivity shrinks so dramatically in just 32 years? This isn’t science fiction—it’s the practical reality of radioactive decay, measured by the isotope’s half-life. With a half-life of just 8 years, the material gradually breaks down over time, transforming scientific theory into clear predictions everyone can understand. Modern discussions around radioactive decay have grown alongside increasing public interest in nuclear energy, medical imaging, environmental safety, and long-term waste management. People increasingly seek clear answers about how unstable materials fade—whether in medical applications, industrial monitoring, or environmental science. Understanding decay patterns helps inform decisions, from healthcare protocols to safety standards and beyond. The half-life of a radioactive isotope is 8 years. A sample initially weighing 640 grams will decay over time. After one half-life (8 years), 320 grams remain. After a second (16 years), 160 grams remain. Each subsequent period cuts the remaining amount in half. Over 32 years—four half-lives—the material reduces to just 40 grams. This predictable transformation follows a simple mathematical model, making it both reliable and accessible for real-world use.