Answer:
The half life of the element = 8 minutes
Explanation:
Solution:
The initial amount = 10g
final amount = 1.25g
elapsed time = 24 minutes
Half life formula
t1/2 = t/(log1/2(Nt/N0))
or (Nt/N0) = 0.5^(t/(t1/2))
or 1.25/10 = 0.5^((24×60)/(t1/2))
Log of both sides gives
0.125 = 0.5^(1440/(t1/2))
-0.903 = 1440/t1/2×log(0.5)
-0.903 = 1440/t1/2×(-0.301)
3 = 1440/t1/2
t1/2 = 1440/3 = 480
Solving we have
t1/2 or the half life = 480s
= 480/60 minutes or
= 8 minutes
