The answer is : 17.5 liters drained and replaced by 17.5 liters of 100% solution.
x = amount drained and replaced
(70-x) = remaining amount of 20% solution
<span>.20(70-x) + 1.00(x) = .40(70)
14 - .2x + 1x = 28
1x - .2x = 28 - 14
</span><span>.8x = 14
</span><span>x = 14/.8
x= 17,5 ( 17.5 liters drained and replaced by 17.5 liters of 100% solution)
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H2O is a compound. So it's second one.
I believe this a PV = nRT question whereas
you re write the formula and solve for volume
V = nRT/ P
then you input the values
P= pressure constant
V= x
n = moles = 0.2540
R = gas constant should be 8.314J mol
T = C degrees + 273.15 = K
solve for voume
make sure all units match
and use sig figs!!!!
