Which diagram best represents the percentage of this radioactive isotope sample that will remain after 2 half-lives? Chemistry, Physics. Played 0 times. Print Share Edit Delete. Live Game Live. Finish Editing.
31.5: Half-Life and Activity
Half Life and Radiometric Dating - Physics | OpenStax
Use this decay calculator to easily calculate the time elapsed since the beginning of the decay, or calculate the original quantity, half-life or remaining quantity of a substance subject to radioactive decay, based on any of the three parameters. Convert half-life to mean lifetime or decay constant, and vice versa by entering any of the three values in its respective field. Our versatile radioactive decay calculator supports many different time units and automatically converts them if the time unit you measure the time elapsed is different than the time unit you enter the half-time, decay constant or mean lifetime in. Supported units are nanoseconds, milliseconds, seconds, minutes, hours, days, weeks, months, and years.
Half-Life and Radioactive Dating Question?
Unstable nuclei decay. However, some nuclides decay faster than others. For example, radium and polonium, discovered by Marie and Pierre Curie, decay faster than uranium. That means they have shorter lifetimes, producing a greater rate of decay. Here we will explore half-life and activity, the quantitative terms for lifetime and rate of decay.
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 material to decrease by one-half. The radioactive isotope cobalt , which is used for radiotherapy , has, for example, a half-life of 5. Thus after that interval, a sample originally containing 8 g of cobalt would contain only 4 g of cobalt and would emit only half as much radiation. After another interval of 5. Neither the volume nor the mass of the original sample visibly decreases, however, because the unstable cobalt nuclei decay into stable nickel nuclei, which remain with the still-undecayed cobalt.