The equivalent weight of $Fe$ in $Fe_2O_3$ is $(Atomic \ mass \ of \ Fe = 56 \ g \ mol^{-1})$

The equivalent weights of $H_3PO_4$ in the following reactions are respectively:
$H_3PO_4 + OH^{-} \rightarrow H_2PO_4^- + H_2O$
$H_3PO_4 + 2OH^{-} \rightarrow HPO_4^{2-} + 2H_2O$
$H_3PO_4 + 3OH^{-} \rightarrow PO_4^{3-} + 3H_2O$

The equivalent weight of phosphoric acid $(H_3PO_4)$ in the reaction $NaOH + H_3PO_4 \to NaH_2PO_4 + H_2O$ is

Atomic weight of $Ne$ is $20.2$. If $Ne$ is a mixture of $Ne^{20}$ and $Ne^{22}$,what is the percentage abundance of the lighter isotope?

The density of liquid ethanol is $0.929 \, g \, cm^{-3}$. What is the volume occupied by one mole of ethanol molecules?

Statement $1$: The equivalent mass of $Cu$ in $CuO$ is $63.6$ and in $Cu_2O$ is $31.8$. Statement $2$: Equivalent mass = $\frac{\text{Molecular mass}}{\text{Valency}}$