# How many years would it take half of the rubidium?

## How many years would it take half of the rubidium?

The method is applicable to very old rocks because the transformation is extremely slow: the half-life, or time required for half the initial quantity of rubidium-87 to disappear, is approximately 50 billion years.

## What is the half-life of SM 147?

List of isotopes

Nuclide Z Half-life
Excitation energy
147Sm 62 1.06(2)×1011 y
148Sm 62 7(3)×1015 y
149Sm 62 Observationally Stable

What is the longest half-life?

The half-life of xenon-124 — that is, the average time required for a group of xenon-124 atoms to diminish by half — is about 18 sextillion years (1.8 x 10^22 years), roughly 1 trillion times the current age of the universe. This marks the single longest half-life ever directly measured in a lab, Wittweg added.

### How long is the half-life of oxygen?

Isotopes

unstable isotopes
mass half-life
oxygen 20 13.51 seconds
21 3.42 seconds
22 2.25 seconds

### Which isotope would be best to date the oldest rock on Earth?

The best-known radiometric dating method involves the isotope carbon-14, with a half life of 5,730 years.

What percentage of rubidium-87 will be left after four half lives?

Since 25% of the Rubidium-87 remains, approximately two half-lives have passed. After one half-life about 50% remains, and after a second half-life 50% of that 50% which is 25% remains.

The radioactive decay of 147Sm into 143Nd and 146Sm into 142Nd through time has produced variations in Nd isotope ratios in terrestrial and extraterrestrial materials.

#### What is the half-life of samarium?

46.3 hours
Samarium 153 is a man-made radionuclide that emits beta particles of 0.81 MeV (20%), 0.71 MeV (30%), and 0.64 MeV (50%) and gamma photons of 103 keV (28%). It has a relatively short half-life of 46.3 hours and, consequently, a relatively high dose-rate.

What material has the shortest half-life?

Uranium-234 has the shortest half-life of them all at 245,500 years, but it occurs only indirectly from the decay of U-238. In comparison, the most radioactive element is polonium. It has a half-life of a mere 138 days. Still, uranium has explosive potential, thanks to its ability to sustain a nuclear chain reaction.

## What is the longest decay chain?

Bismuth-209 was long thought to have the heaviest stable nucleus of any element, but in 2003, a research team at the Institut d’Astrophysique Spatiale in Orsay, France, discovered that 209Bi undergoes alpha decay with a half-life of approximately 19 exayears (1.9×1019, approximately 19 quintillion years), over a …

## Is oxygen 16 stable or unstable?

Oxygen-16 (16O) is a stable isotope of oxygen, having 8 neutrons and 8 protons in its nucleus. It has a mass of 15.99491461956 u. Oxygen-16 is the most abundant isotope of oxygen and accounts for 99.762% of oxygen’s natural abundance.

Is oxygen 17 stable or unstable?

There are three known stable isotopes of oxygen (8O): 16O, 17O, and 18O.