If a radioactive isotope has a half-life of 31 years. What is the decay rate constant in inverse years.

Question

Chemistry 

Answer 1

Assuming the decay is a first order reaction, then...

t_1/2 = 0.693/k

31 yrs = 0.693/k

k = 0.693/31 yrs

k = 0.022 yrs^-1