Question

What is the molarity of KMnO₄ in a solution of 0.0908 g of KMnO₄ in 0.500 L of solution?

a) 0.05 M
b) 0.10 M
c) 0.15 M
d) 0.20 M

Answer 1

To find the molarity of KMnO₄, calculate the moles using the mass and molar mass, then divide by the volume of solution. The molarity is 1.15 x 10⁻³ M.

Step-by-step explanation:

To calculate the molarity of KMnO₄ in a solution, you need to follow these steps:

1. Determine the molar mass of KMnO₄.
2. Calculate the number of moles of KMnO₄ using the given mass.
3. Use the number of moles and the volume of the solution to find the molarity.

Molar mass of KMnO₄ = 39.1 (K) + 54.9 (Mn) + 4 × 16.0 (O) = 158 g/mol. Therefore, moles of KMnO₄ = 0.0908 g / 158 g/mol = 5.75 x 10⁻´ moles.

Molarity (M) = moles of solute / liters of solution. Thus, Molarity = 5.75 x 10⁻´ moles / 0.500 L = 1.15 x 10⁻³ M.

The molarity of KMnO₄ in the given solution is 1.15 x 10⁻³ M.