Question

Define half—life of a radioactive element and obtain its formula.

Answer 1

Answer:

I don't know the formula ( you can google it) but I can explain you what is half life of a radioactive element.

Half-Life is a period in which the radioactive element gets halved in quantity...

i.e. for example , a 100 gram radioactive element have a half life of 5 years.

So, after 5 years it will become 50 grams.

in next 5 years the amount will be reduced to 25 grams.

Similarly, for another five years the amount remaining will be 12.5 grams.

So, accordingly you can say that the radioactive element can never be 100% destroyed.

Answer 2

Explanation:

A radioactive half-life relates to how long it takes to decline for half of the initial isotope. For instance, if a 50.0 gram sample's half-life is 3 years, then only 25 grams would stay in 3 years. 12.5 grams would stay for the next 3 years, and so on.

It is calculated as -

In.Nt/No = -kt

Where - Nt is the mass of the radioactive material at the time interval (t)

No is the mass of original amount of the radioactive material

k is the decay constant  and

t is the time interval ie. t1/2 for the half-life