Answer:
46.4 mL
Step-by-step explanation:
The trick here is to use the known volume by volume percent concentration,
v/v%
, to figure out how many milliliters of isopropanol, the solute, are present in your sample.
Now, the thing to remember about volume by volume percent concentrations is that they are meant to represent the number of milliliters of solute present for every
100 mL
of solution.
In your case, the solution contains
74.3
%
v/v isopropanol
=
74.3 mL
.
isopropanol in
.
100 mL
.
solution
As you know, solutions are homogeneous mixture, which implies that they have the same composition throughout.
This means that you can use solution's volume by volume percent concentration to calculate the number of milliliters of isopropanol present in
62.4 mL
of solution.
Set up the equation as
?
.
mL solute
62.4 mL solution
=
74.3 mL
.
solute
100 mL
.
solution
Rearrange and solve to find
?
=
62.4
mL solution
100
mL solution
⋅
74.3 mL solute
?
=
46.36 mL solute
Rounded to three sig figs, the answer will be
volume isopropanol = 46.4 mL
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