What are the formulas for half-life in exponential decay?
The formulas for half-life are
The equation for exponential decay is
We can solve this for
And the formulas for half-life
If you know the value of
Technetium-99m is used for brain scans. If a laboratory receives a shipment of
200 g of this isotope and only 12.5 g of this isotope remain after 24 h, what is the half-life of technetium-99m?