35.2: Introduction
- Page ID
- 29319
\( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \) \( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)\(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\) \(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\)\(\newcommand{\AA}{\unicode[.8,0]{x212B}}\)
Radioactive decay is the process of an atom changing into a different type of atom; it is a change in the number of protons. Half-life is the time it takes for one half of a sample of radioactive atoms to decay, so that half of the original number of atoms have decayed. Each radioactive isotope has its own half-life. The half-life of an isotope of carbon may be used to determine the age of a fossil. The amount of a radioactive isotope remaining in a sample indicates the approximate age of the sample.
|
Radioactive Isotope |
Half-life |
|---|---|
|
\(\ce{_{94}^{239}Pu}\) |
24,400 years |
|
\(\ce{_{92}^{238}U}\) |
4.51 x 109 years |
|
\(\ce{_{84}^{214}Po}\) |
0.00016 seconds |
|
\(\ce{_{83}^{210}Bi}\) |
5 days |
|
\(\ce{_{82}^{210}Pb}\) |
20.4 years |
|
\(\ce{_{6}^{14}C}\) |
5,730 years |