Question

6) 0.1 N oxalic acid can be prepared
can be prepared by dissolving
g of oxalic acid in 250 ml of
measuring flask *
16 g
O 1.69
O 0.16g
O 160g​

Answer 1

We need to prepare 250 mL of 0.1 N Oxalic acid solution.

Formula of Oxalic acid = H2C2O4.2H2O (Dihydrate)

Basicity of Oxalic acid = 2 (2 H+ ions per molecule of the acid on complete dissociation in aqueous state.)

Normality = Basicity x Molarity (For an acid solution)

0.1 = 2 x Molarity

=> Molarity = 0.1/2 => 0.05 M

Volume of Oxalic acid solution = 250 mL => 250/1000 L => 0.25 litres

Molarity = (no. of moles of solute)/(litres of solution)

0.05 = (no. of moles)/0.25

=> no. of moles of H2C2O4 = 0.05 x 0.25 => 0.0125 moles of H2C2O4.

=> Molar mass of Oxalic acid is 126 grams per mole.

=> So, 0.0125 moles has a mass of 0.0125 x 126 g =>  1.575 grams.

Hence, 1.575 grams of Oxalic acid must be dissolved.