Question

For the reaction: $2Fe{S_2} + \dfrac{{11}}{2}{O_2} \to F{e_2}{O_3} + 4S{O_2}$ . What will be the equivalent of $Fe{S_2}$ ,if the molecular weight of $Fe{S_2}$ is M?
1) $\dfrac{M}{8}$
2) $M$ .
3) $\dfrac{M}{{11}}$.
4) Can’t be calculated.

Answer 1

Hint: We need to remember that the equal weight is the mass of one same that is the mass of a given substance which will join with or uproot a fixed amount of another substance. The comparable load of a component is the mass which joins with or uproots \[1.008\] gram of hydrogen or \[8.0\] grams of oxygen or \[35.5\] grams of chlorine. These qualities compare to the nuclear weight separated by the standard valence; for oxygen as a model that is\[\dfrac{{16.0g}}{2} = 8.0g\] .

Complete step by step answer:
The balanced chemical reaction is,
$2Fe{S_2} + \dfrac{{11}}{2}{O_2} \to F{e_2}{O_3} + 4S{O_2}$
From the reaction it is found that one mole of $Fe{S_2} = \dfrac{{11}}{4}$ moles of oxygen.
This means that each oxygen ion takes two electrons for reduction. Thus one oxygen molecule takes four electrons.
Let us calculate the number of electrons gained by oxygen,
${O_2} = \dfrac{{11}}{4} \times 4 = 11$
The number of electrons lost by $Fe{S_2}$ is eleven.
Thus, the equivalent weight of $Fe{S_2}$ is $\dfrac{M}{{11}}$.
Thus option 3 is correct.

Note:
We must need to know that for acid base responses, the comparable load of a corrosive or base is the mass which supplies or responds with one mole of hydrogen cations. For redox responses, the comparable load of every reactant supplies or responds with one mole of electrons in a redox reaction. Comparable weight has the measurements and units of mass, in contrast to nuclear weight, which is dimensionless. Equal loads were initially controlled by analysis, yet are currently gotten from molar masses. Also, the identical load of a compound can be determined by isolating the sub-atomic mass by the quantity of positive or negative electrical charges that result from the disintegration of the compound.