What is the molarity of a sodium chloride solution that contains #"3.8 moles"# of sodium chloride in #"2.5 L"# of the solution?
The problem provides you with the composition of a sodium chloride solution in terms of moles of solute and total volume of solution.
In order to find the solution's molarity, all you have to do is figure out how many moles of solute would be present in
You already know that
You can thus say that you have
#1 color(red)(cancel(color(black)("L solution"))) * overbrace("3.8 moles NaCl"/(2.5color(red)(cancel(color(black)("L solution")))))^(color(blue)("known composition")) = "1.52 moles NaCl"#
Since one liter of solution contains
#color(green)(|bar(ul(color(white)(a/a)color(black)(c = "1.5 mol L"^(-1))color(white)(a/a)|)))#
The answer is rounded to two sig figs.