Question

The time necessary for the decay of one- half sample of a radioactive substance is a _____. mass defect daughter half life nuclide

Answer 1

The time necessary for the decay of one- half sample of a radioactive substance is a half-life.

Answer 2

Answer: half life

Explanation: Radioactive decay follows first order kinetics and the time required for the decay of a radioactive material is calculated as follows:

`t=(2.303)/(k)\hspace{1mm}log(x)/(a)`

t= time required

k= disintegration constant

x= amount of substance left after time t

a= initial amount of substance

when one half of the sample is decayed, one half of the sample remains and t can be represented as
`t_(1/2)`

at
`t= t_(1/2)`,
`x=(a)/(2)`

`t_(1/2)=(2.303)/(k)\hspace{1mm}log(a/2)/(a)`

`t_(1/2)=(0.693)/(k)`