Radioactive isotopes are used in nuclear medicine to allow physicians to explore bodily structures in patients. Very small quantities of these, isotopes, such as iodine-131 (I-131; half-life 8.065 days), are injected into patients. The isotopes are traced through the body so a medical diagnosis can be made. These elements have a very short half-life, so the label on the bottle will state the radioactivity of the element (the amount of the element that remains) at a particular moment in time.
b) Effective half-life is the time required for a radioactive isotope contained in a body to reduce its radioactivity by half, due to a combination of radioactive decay and the natural elimination of the isotope from the body. In patients with Graves disease, the effective half-life of I-131 is
of the normal half-life. In patients with a disease called toxic nodular goitre, the effective half-life is
of the normal half-life. Compare these results to the standard rate of decay for I-131 numerically, graphically, and algebraically