Question

Half-life period of ${}_{79}A{u}^{198}$ nucleus is 150 days. The average life is:

• A. 216 days
• B. 21.6 days
• C. 361 days
• D. 26.1 days

Answer 1

The correct option is A 216 days

The radioactive half-life for a given radioisotope is the measure of the tendency of the nucleus to "decay" or "disintegrate" and as such is based purely upon that probability. The half-life is independent of the physical state (solid, liquid, gas), temperature, pressure, the chemical compound in which the nucleus finds itself, and essentially any other outside influence.

Average life, $t_{avg}=\frac{Halflife}{ln2}=\frac{150}{.693}=216days$