<u>Answer:</u> The balanced chemical equation is written below.
<u>Explanation:</u>
Double displacement reaction is defined as the reaction in which exchange of ions takes place.

When sodium permanganate reacts with iron (III) chloride, it leads to the production of sodium chloride and iron (III) permanganate.
The chemical equation for the reaction of sodium permanganate and iron (III) chloride follows:

By Stoichiometry of the reaction:
3 moles of aqueous solution of sodium permanganate reacts with 1 mole of aqueous solution of iron (III) chloride to produce 1 mole of solid iron permanganate and 3 moles of aqueous solution of sodium chloride
Hence, the balanced chemical equation is written above.
From the chemical formula the total mass of the compound can be determined. The mass of the 1 mole of the compound is its molar mass. The atom by which the molecule is generated, the mass of these atoms are expressed in terms of amu or atomic unit mass, but after formation of a molecule in a particular ratio the mass of each of the atom becomes the total molecular weight of the generated molecule. In this case the molecule posses three atoms X, Y and Z which are in a ratio of 2:2:7. Thus the chemical formula of the compound can be written as
.
So the total mass of the compound in amu is {(2×47)+(2×42)+(7×16)} = {94+84+112}=290 amu.
Thus 1 mole of the compound contains 290 amu or 290 g by mass.
Henceforth 20 gram of the compound is equivalent to (20/290) = 0.068 mole.
Answer:
I'm a bit confused on where the question is. Perhaps re-write it in the comments? I'd love to help but this seems more like an answer than a question xD
Explanation: