How many moles of NaCl are contained in 467 mL of a .244M solution of NaCl?

1 Answer
Dec 12, 2015

"0.144 moles"

Explanation:

As you know, molarity is defined as the number of moles of solute, which in your case is sodium chloride, "NaCl", divided by liters of solution.

color(blue)("molarity" = "moles of solute"/"liters of solution")

Simply put, dissolving one mole of a solute in one liter of solution will produce a "1.00-M" solution.

In your case, the volume of the solution is said to be equal to "467 mL" and the molarity of the solution to "0.244 M". Since molarity tells you number of moles per liter, you can say that you will get "0.244 moles" of sodium chloride in one liter of this solution.

Since you have a little less than half of a liter, i.e. "467 mL", you can expect to have fewer than half of "0.244 moles".

More specifically, the solution will contain - do not forget to convert the volume of the solution from milliliters to liters!

color(blue)(c = n/V implies n = c * V)

n = 0.244 "moles"/color(red)(cancel(color(black)("L"))) * 467 * 10^(-3) color(red)(cancel(color(black)("L"))) = "0.1139 moles NaCl"

Rounded to three sig figs, the answer will be

n_(NaCl) = color(green)("0.114 moles")

SIDE NOTE Because sodium chloride dissociates completely in aqueous solution, you wouldn't actually say that you have a "0.244 M" sodium chloride solution.

Instead, you would say that you have a solution that is "0.244 M" in sodium cations, "Na"^(+), and "0.244 M" in chloride anions, "Cl"^(-).