he plant started to purify its wastewater before discharging it into the lake. How long will...
he plant started to purify its wastewater before discharging it into the lake. How long will it take for the concentration of the chemical to reduce to 1% of its steady-state value, if its half-life is 2 years?
Homework Answers
The formula is given as A= A0(1/2)^(t/h)
h is half life and A is the final concentration.
A= 1, A0 = 100
1 = 100 (0.5)^(t/2)
0.01 = 0.5^(t/2)
Taking ln on both sides,
ln (0.01)= (t/2) ln(0.5)
-4.605 = (t/2) (-0.693)
t = 13.29 hrs
Time taken for the decay = 13.29 hrs
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