# What is half-life of radioactive elements?

## What is half-life of radioactive elements?

Half-life, in radioactivity, the interval of time required for one-half of the atomic nuclei of a radioactive sample to decay (change spontaneously into other nuclear species by emitting particles and energy), or, equivalently, the time interval required for the number of disintegrations per second of a radioactive …

How do you find the half-life of a radioactive element?

So, if a problem asks you to calculate an element’s half-life, it must provide information about the initial mass, the quantity left after radioactive decay, and the time it took that sample to reach its post-decay value. Therefore, its half-life is t1/2=98.012.7=7.72 years .

### How many half lives is 3?

Explanation: Three half lives corresponds to (12)3 . So a 18 quantity of the original isotope is retained.

Which element has the longest half life?

nvm problm solved: I finally found the element with longest half life, as stated in my element book,” Uranium is the last and heaviest of the natural elements” (203). “its half-life of 4.6 billion years makes it the longest-lived of all isotopes.

#### What element has half life?

Cesium-137 is a radioactive element with a half-life of thirty years. Its decay results in the formation of Ba-137 with a very short half-life. Both elements have the same atomic mass but cesium has an atomic number of 55 and barium has an atomic number of 56.

What is the half life of radioactive material?

The term half-life is defined as the time it takes for one-half of the atoms of a radioactive material to disintegrate. Half-lives for various radioisotopes can range from a few microseconds to billions of years.

## What is an example of a half life?

The half-life is the length of time that it takes for half of an initial sample to undergo a change. Usually this is the radio-active decay of a specific atomic weight of an element. For example, the half-life of Uranium-238 is 4.46 billion years.