Reductant is also known as reducing agent means it helps in the reduction process by losing electrons from itself.
In Ferrous sulphate, , iron (Fe) is present in +2 oxidation state and sulphur is present in the -2 oxidation state. When ferrous sulphate is present as reductant, it removes one electron and turns into +3 oxidation state.
Molecular weight of is:
Equivalent weight of ferrous sulphate is
So, equivalent weight of ferrous sulphate is equal to the molecular weight of ferrous sulphate.