What is the volume of solution with 0.82g/L concentration when the mass of the solute is 7g?

1 Answer
Feb 3, 2018

#"9 L"#


The idea here is that the concentration of the solution tells you the number of grams of solute present for every #"1 L"# of the solution.

This solution is said to have a concentration of #"0.82 g L"^(-1)#, which means that #"1 L"# of this solution will contain #"0.82 g"# of solute.

Now, you know that you have a sample of this solution that contains #"7 g"# of solute. As you know, a solution is a homogeneous mixture, which implies that it has the same composition throughout.

Consequently, you can use the concentration of the solution to determine how many liters would contain #"7 g"# of solute.

#7 color(red)(cancel(color(black)("g solute"))) * overbrace("1 L solution"/(0.82color(red)(cancel(color(black)("g solute")))))^(color(blue)("= 0.82 g L"^(-1))) = color(darkgreen)(ul(color(black)("9 L solution")))#

The answer is rounded to one significant figure, the number of sig figs you have for the mass of the solute.