Answer:
The key to this problem lies with the definition of percent concentration by mass,
m/m %
.
As you know, percent concentration by mass is defined as the ratio between the mass of the solute and the total mass of the solution, multiplied by
100
.
% m/m
=
mass of solute
mass of solution
×
100
You are told that your bleach solution has a
3.62
%
percent concentration by mass. Looking at the above definition, that should tell you that every
100 g
of solution will contain
3.62 g
of sodium hypochlorite, your solute.
In your case, the mass of the solution is said to be equal to
1500.0 g
. This means that it will contain
1500.0
g solution
⋅
3.62 g NaOCl
100
g solution
=
54.3 g NaOCl
Alternatively, you can use the equation for percent concentration by mass to find the mass of the solute
% m/m
=
m
solute
m
solution
×
100
m
solute
=
%m/m
⋅
m
solution
100
Plug in your values to get
m
solute
=
3.62
⋅
1500.0 g
100
=
54.3 g NaOCl
