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half-life

AI overview

Half-life is the amount of time it takes for half of a radioactive substance to decay or break down. This concept matters because it allows scientists to predict how quickly radioactive materials will diminish over time and to determine the age of ancient objects.

AI-generated from the Wikipedia summary — may contain errors.

Article

13 sections

Contents

Probabilistic nature
Formulas for half-life in exponential decay
Half-life and reaction orders
Zero order kinetics
First order kinetics
Second order kinetics
Decay by two or more processes
Examples
In non-exponential decay
In biology and pharmacology
See also
References
External links

{| class="wikitable" align=right ! Half-liveselapsed !! Fractionremaining !! colspan=2| Percentageremaining |- | 0 || ||align=right style="border-right-width: 0; padding-right:0"| 100||style="border-left-width: 0"| |- | 1 || ||align=right style="border-right-width: 0; padding-right:0"| 50||style="border-left-width: 0"| |- | 2 || ||align=right style="border-right-width: 0; padding-right:0"| 25||style="border-left-width: 0"| |- | 3 || ||align=right style="padding-right:0; border-right-width: 0"| 12||style="border-left-width: 0; padding-left:0"|.5 |- | 4 || ||align=right style="border-right-width: 0; padding-right:0"| 6||style="border-left-width: 0; padding-left:0"|.25 |- | 5 || || align=right style="border-right-width: 0; padding-right:0"|3||style="border-left-width: 0; padding-left:0"|.125 |- | 6 || || align=right style="border-right-width: 0; padding-right:0"|1||style="border-left-width: 0; padding-left:0"|.5625 |- | 7 || ||align=right style="border-right-width: 0; padding-right:0"| 0||style="border-left-width: 0; padding-left:0"|.78125 |-

|- | || || colspan=2| |}