The correct option is C 40 mL
Number of moles of oxalic dihydrate, C2H2O4.2H2O=6.3126=0.05
Molarity of oxalic acid solution
=0.05250×1000=0.2 M
Since, the resultant solution will be neutral, and 1 mol of oxalic acid gives 2 mol of H+ ion.
So, M1V1=M2V2
Where M1 and V1 are the molarity of H+ ion and the volume of the acid solution.
M2 and V2 are the molarity of OH− ion and the volume of the basic solution.
(2×0.2×10)=(0.1×V2)
On solving, volume = 40 mL
Therefore, 40 mL of 0.1 M NaOH is required to neutralize the oxalic acid solution.