Question

Determine the mass of NaCl in 1.0 L of 3.0 % by mass aqueous solution of sodium chloride. The density of the solutions is 1.10 gmL-1

please explain all the steps, thanks!

Answer 1

3.0% NaCl by mass means 3.0 g NaCl/100 g solution and that is the same as 30.0 g NaCl/1,000 g solution. That consists of 30.0g NaCl/(30.0g NaCl + 970 g H2O)
The 1000g soln has a volume of 1000/1.10 = 909.091.
So if we had a L of the solution, the amount of NaCl would be
30.0 g x (1000 mL/909.091 mL) = ??

Answer 2

That consists of 30.0g NaCl/(30.0g NaCl + 970 g H2O)
...........

Where did this # come from 970 g H2O?

Answer 3

I meant to erase that and thought I did because I thought it might confuse you; however, the 970 g is a correct number but you don't need it anywhere. Where does it come from?
30.0g NaCl/1000 g solution = 30.0g NaCl/(30 g NaCl + 970 g H2O) but you never need the 970g for anything (unless you just wanted to know how much of the solution was water and how much was NaCl.).

Answer 4

Ok Thanks =)