When Ferrous sulphate acts as reductant, its equivalent weight is

Reductant is also known as reducing agent means it helps in the reduction process by losing electrons from itself.

In Ferrous sulphate, $$\text{FeS}{\text{O}}_{\text{4}}$$, 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 $$\text{FeS}{\text{O}}_{\text{4}}$$ is:
$$\begin{array}{c}\text{FeS}{\text{O}}_{\text{4}}=55.8+32+(4\times 16)\\ \text{FeS}{\text{O}}_{\text{4}}=151.8\end{array}$$

Equivalent weight of ferrous sulphate is
$$\text{FeS}{\text{O}}_{\text{4}}={\displaystyle \frac{151.8}{1}}=151.8$$
So, equivalent weight of ferrous sulphate is equal to the molecular weight of ferrous sulphate.