Question bank/JEE Advanced/Chemistry

$5.00 \mathrm{~mL}$ of $0.10 \mathrm{M}$ oxalic acid solution taken in a conical flask is titrated against $\mathrm{NaOH}$ from a burette using phenolphthalein indicator. The volume of $\mathrm{NaOH}$ required for the appearance of permanent faint pink color is tabulated below for five experiments. What is the concentration, in molarity, of the $\mathrm{NaOH}$ solution?



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Exp. No.	Vol. of NaOH (mL)
$\mathbf{1}$	12.5
$\mathbf{2}$	10.5
$\mathbf{3}$	9.0
$\mathbf{4}$	9.0
$\mathbf{5}$	9.0

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Source: JEEBench (IIT Delhi) / JEE Adv 2020 Paper 1