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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3rd one:
it is very reactive because it does not have a full Valence shell.
this is because it's in group 1 so it has one electron in its outer shell, and it wants to have a full outer shell ( which it can gain by losing the electron in a reaction).
Hope this helps :)
The molecular mass of carbon monoxide (CO) is 28 g/mol
<u><em>calculation</em></u>
The molecular mass of CO = atomic mass of C + atomic mass of O
From periodic table the atomic mass of C = 12 g/mol and for O = 16 g/mol
Therefore the molecular mass of Co = 12 g/mol + 16 g/mol = 28 g/mol