Question

Calculate the amount in moles and grams of KMnO4 present in 3dm^3 of 0.25M​

Answer 1

Number of moles = 0.75 mol

Mass = 118.5 g

Step-by-step explanation:

Given data:

Number of moles of KMnO₄ = ?

Mass in gram = ?

Molarity of KMnO₄ = 0.25 M

Volume of KMnO₄ solution = 3 dm³ (3 L)

Solution:

Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.

Formula:

Molarity = number of moles / L of solution

0.25 M = number of moles / 3 L

Number of moles = 0.25 M× 3 L

M = mol/L

Number of moles = 0.75 mol

Mass in gram:

Mass = number of moles × molar mass

Mass = 0.75 mol × 158 g/mol

Mass = 118.5 g