They are found deep within the earth. (Fossil fuels are the main cause of pollutions, they do not form quickly, and they are non-renewable resources.)
Solutions for your questions are the following:
1. remaining amount is equal to:960 g : 100% = 30 g : xx = 30 g * 100% / 960 g
= 3.125%
= 0.03125
Now, we use this formula to calculate the number of half-lives:(1/2)ⁿ = x,
so,(1/2)ⁿ = 0.03125
to calculate n, use this equation:
n*log(1/2) = log(0.03125) n = log(0.03125)/log(1/2)
= log(0.03125)/log(0.5)
= -1.505/-0.301
n=5
Ifn = 5T = 15 min
Then
L = T/nL = 15 min/5
= 3 minutes
2. You should pick filtration. It is use to separate heterogeneous mixtures just like in the problem stated.
