I'm trying to find concentration of NaOCl and it says to convert the 10% by weight stock solution to a molarity assuming the density of the solution is that 1.00 g/mL. I am confused with the 10% by weight part so if someone could help explain that part that would be great! Thanks in advance!!
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10% mass weight by weight means , that the weight of solute is 10% of the mass of total solution
I give you the formula
% w/w = 100*weight of solute/weight of solution
in your example 1 liter of the solution weighs 1000g
NaOCl (w/w) =10% =0.1
so the weight o the solute is 1000 *0.1=100g
The molar weight of NaOCl is 23+16+35.5=74.5g
the normality of the solution is 100/74.5=1.34M
I give you the formula
% w/w = 100*weight of solute/weight of solution
in your example 1 liter of the solution weighs 1000g
NaOCl (w/w) =10% =0.1
so the weight o the solute is 1000 *0.1=100g
The molar weight of NaOCl is 23+16+35.5=74.5g
the normality of the solution is 100/74.5=1.34M
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That means the weight of the salt is 10% of the weight of the solution. Some mixtures are specified as % by volume, which is meaningless if the volumes change when they are mixed.