Question

calculate the number of moles of hydrated oxalic acid in 100ml of 0.2N oxalic acid​

Answer 1

Answer:

Explanation:Step I. Calcualtion of mass of oxalic acid

Normality of solution =Mass of oxalic acid/Equivalent massVolume of solution in litres

Normality of solition =0.2N=0.2equiv. L−1

Equivalent mass of acid =Molar massBasicity=2×1+2×12+4×16+2×182=1262=63g equiv.−1

Volume of solution =100mL=1001000=0.1L

∴(0.2 equiv. L−1)=Mass of oxalic acid(63 g equiv−1)×(0.1 L)

Mass of oxalic acid =(0.1equiv. L−1)×(63 equiv.−1)×(0.1L)=1.26g

Step II. Calculation of no of molecules of oxalic acid

Molar mass of oxalic acid =126gmol−1

Now, 126 g oxalic acid has molecules = Avogadro No. =6.022×1023

1.26 g of oxalic acid has molecules =6.022×1023(126g)×(1.26g)=6.022×1021.