The radioactive substance krypton-91 has a very short half-life of about 10 seconds. What is the decay constant for this substance?

Question

I've been struggling with this question for about two days now. I'm not understanding what information I have and what equation to put it into..

Answer 1

Hi Sierra,

 

The information given is your half life, t_1/2=10 seconds. The decay constant, usually denoted by λ, is given by

 

λ = ln(2)/t_1/2

   = 0.693/10 seconds

   = 0.0693 per second.

 

That equation is always the one used for the decay constant. Hope this helps!