The molecular weight of Potassium permanganate (KMnO₄) is 158.033943.

Potassium permanganate (KMnO4) is an inorganic compound of three elements: Potassium Manganese, and Oxygen. The molecular weight of Potassium permanganate (KMnO4) is 158.033943 which can be calculated by adding up the atomic weight of Potassium, Manganese and Oxygen.

To calculate molecular weight of any compound, the first step is to know the constituent elements (atoms) and their number in that particular compound. Then calculate the total atomic weight of each element by multiplying its atomic weight by its number. The sum of total atomic weight of all constituent elements will be the molecular weight of the compound. Note that the value of atomic weight may differ from different sources.

CALCULATION PROCEDURE: Potassium Permanganate [KMnO4] Molecular Weight Calculation

Step 1: Find out the chemical formula and determine constituent atoms and their number in a Potassium permanganate molecule.
From the chemical formula, you will know different atoms and their number in a Potassium permanganate molecule. The chemical formula of Potassium permanganate is KMnO₄. From the chemical formula of Potassium permanganate, you can find that one molecule of Potassium permanganate has one Potassium (K) atom, one Manganese (Mn) atom, and four Oxygen (O) atoms.

Step 2: Find out the atomic weights of each atom (from the periodic table).

Atomic weight of Potassium (K): 39.0983 (Ref: Ciaaw-potassium)
Atomic weight of Manganese (Mn): 54.938043 (Ref: Ciaaw-manganese)
Atomic weight of Oxygen (O): 15.9994 (Ref: Jlab-ele008)

Step 3: Calculate the molecular weight of Potassium permanganate by adding the total weight of all atoms.

Number of Potassium atoms in Potassium permanganate: 1
Atomic weight of Potassium: 39.0983
Total weight of Potassium atoms in Potassium permanganate: 39.0983

Number of Manganese (Mn) atoms in Potassium permanganate: 1
Atomic weight of Manganese: 54.938043 x 1 = 54.938043
Total weight of Manganese atoms in Potassium permanganate: 54.938043

Number of Oxygen (O) atoms in Potassium permanganate: 4
Atomic weight of Oxygen: 15.9994
Total weight of Oxygen atoms in Potassium permanganate: 15.9994 x 4 = 63.9976

Step 4: Calculate the molecular weight of Potassium permanganate by adding up the total weight of all atoms.

Molecular weight of Potassium permanganate : 39.0983 (Potassium) + 54.938043 (Manganese) + 63.9976 (Oxygen) 

So the molecular weight of Potassium permanganate is 158.033943.

Potassium Permanganate [KMnO4] Molecular Weight Calculation

REFERENCES:

• Ciaaw-potassium : https://www.ciaaw.org/potassium.htm
• Ciaaw-manganese: https://www.ciaaw.org/manganese.htm
• Jlab-ele008: https://education.jlab.org/itselemental/ele008.html

See also:

• Hydrogen chloride molecular weight calculation