Question

Strontium-90 has a half life of 29 years, how much strontium-90 is left from the Chicago pile reactor that was active around 87 years ago.

Answer 1

The answer is below

Step-by-step explanation:

The half life of a substance is the time required by that substance to reduce to half of its initial value. The half life is calculated using the formula:

`N(t)=N_o((1)/(2) )^(t)/(t_(1)/(2) ) \\\\where\ N(t)=quantity\ of\ substance \ remaining, N_o=initial\ quantity\\of\ substance, t=time\ and \ t_(1)/(2)=half\ life\ of\ substance`

Given that t = 87 years, half life = 29 years, therefore the quantity of strontium-90 left is:

`N(t)=N_o((1)/(2) )^(87)/(29) \\\\N(t)=N_o((1)/(2) )^(t)/(t_(1)/(2) ) \\\\N(t)=N_o((1)/(2) )^3\\\\N(t)=(1)/(8) N_o`

That is one-eight of Strontium 90 would be left after 87 years