Question #18314

1 Answer
Jun 20, 2017

Answer:

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")#