# science(chem)

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How would I make a 5% solution of sodium bisulfite?

sodium bisulfite: NaHSO3
Molar mass: 104.06 g/mol

is it 5% w/w
or v/v
or w/v

b/c if it was w/w then it would be
weight percent w/w= weight solute/ weight solution* 100

I need help on this

Thanks

• science(chem) -

I have been told several times that it means w/w if w/w or w/v is not specified (you don't mean v/v because NaHSO3 is a solid). However, for your purposes, I doubt if it makes that much difference.

• science(chem) -

Is it 5g of the sodium bisulfite mixed with 100ml of solvent?

• science(chem) -

I mean 5g of sodium bisulfite mixed with 100g of solvent

• science(chem) -

No, w/w is 5 g NaHSO3 + 95 g solvent for 100 g solution.

• life science -

need help on cell cycle

• science(chem) -

but why does the Fundamentals of Analytical Chemistry book state on the w/w page that a "70% solution, which means the reagent contains 70g of HNO3 per 100g of solution" ?

• science(chem) -

I'm not looking at that page; however, look at it this way.
70% solution means that if we take 100 g of solution, 70% (or 70 g will be the solute and 30 g is the solvent to make 100 g of solution. And that is consistent with making a 70% solution of something, w/w.
To make a 70% w/w solution, we take 70 g solute, add 30 g solvent, to make 100 g solution. In your example and my example,we have 100 g of solution.

• science(chem) -

okay

Thanks Dr.Bob