Question

to prepare a 100 ml standard solution of 0.01N strength of oxalic acid, the amount of oxalic acid required is

Answer 1

Normality = Number of gram equivalents of solute / Volume of solution (in litres)

The number of gram equivalents are defined as = mass of solute / equivalent mass
Normality = $\frac{\mathrm{mass}\mathrm{of}solute}{\mathrm{equivalent}mass}\times \frac{1000{\text{mL· L}}^{\text{-1}}}{\text{amount of solvent in mL}}$

Mass of solute = Normality x equivalent mass x $\frac{\text{amount of solvent in mL}}{1000{\text{mL·L}}^{-1}}$ ......(1)

Equivalent mass of oxalic acid = Molar mass of oxalic acid /basicity
= 90 g mol^-1/2
= 45 g eq^-1

Putting all the given values in eq (1) we get:
Mass of solute (oxalic acid required) = 0.01 eq L^-1 x 45 g eq^-1​ x $\frac{\text{100 mL}}{1000{\text{mL·L}}^{-1}}$
= 0.045 g

​Mass of solute (oxalic acid required) = = 0.045 g​