Question

The half – life for the disintegration of radium is 1590 years. Calculate the rate constant
in seconds and also how many years will be taken for the disintegration of 80 percent of the material?

Answer 1

k = 0.693/t<sub>1/2</sub) gives k in years. You can convert that to seconds. I would convert 1590 years to seconds and plug that in to calculate rate in seconds. But use the year calculation above to solve for years. If 80% disintergration then 20% is eft.
ln(No/N) = kt
No = 100
N = 20
k from above in years
t is the unknown. Solve for that in years.

Answer 2

Answer