Question #18314

1 Answer
Jun 20, 2017

The molarity of the "KMnO"_4 solution is "0.01511 mol/L". A container of this solution would be labeled "0.01511 M KMnO"_4", and it would be called a 0.01511 molar potassium permanganate solution.

Explanation:

Molarity ="mol solute"/"L of solution".

You have liters of solution, but you don't have moles of solute, "KMnO"_4" (potassium permanganate).

However, you can determine moles "KMnO"_4 from its given mass and its molar mass, which is "158.0323 g/mol".

To determine the moles of "KMnO"_4", multiply its given mass by the inverse of its molar mass.

4.7744color(red)cancel(color(black)("g KMnO"_4))xx(1"mol KMnO"_4)/(158.0323color(red)cancel(color(black)("g KMnO"_3)))="0.030212 g KMnO"_4"

Now that you have moles of solute and liters of solution, you can calculate molarity using the equation above.

Molarity=(0.030212"mol KMnO"_4)/(2.000"L solution")=("0.01511 mol KMnO"_4)/(1"L solution")