Half Life

[munecaDDS]

So im always getting the half life questions wrong on my practice test and i wanted to know if any one has a method to getting them right . For example in destroyer number 171 states. Consider radioactive nuclide X. If 88% of a pure sample decays in 24 hours,what is the half- life? ... the correct awnser is B 8hrs but i dont understand how ... thanks

---

Members don't see this ad.

 

[Sea of ASH]

ok just think of half-life as arrows

percentage is how much of original is there:

100% -------> 50%-------> 25%--------> 12.5% (all in 24 hours)

what does it mean to be 12.5 percent remaining? 88 percent decay right? so how many arrows did you come up with? 3 right. whats 24 divided by 3? ......