Answer: The molecular weight of the dibasic acid is 89.6 g/mol
Explanation:
Normality is defined as the amount of solute expressed in the number of gram equivalents present per liter of solution. The units of normality are eq/L. The formula used to calculate normality:
[tex]\text{Normality}=\frac{\text{Given mass of solute}\times 1000}{\text{Equivalent mass of solute}\times \text{Volume of solution (mL)}}[/tex] ....(1)
We are given:
Normality of solution = [tex]\frac{1}{20}=0.05N[/tex]
Given mass of solute = 0.56 g
Volume of solution = 250 mL
Putting values in equation 1, we get:
[tex]0.05=\frac{0.56\times 1000}{\text{Equivalent mass of solute}\times 250}\\\\\text{Equivalent mass of solute}=\frac{0.56\times 1000}{0.05\times 250}=44.8g/eq[/tex]
Equivalent weight of an acid is calculated by using the equation:
[tex]\text{Equivalent weight}=\frac{\text{Molar mass}}{\text{Basicity}}[/tex] .....(2)
Equivalent weight of acid = 44.8 g/eq
Basicity of an acid = 2 eq/mol
Putting values in equation 2, we get:
[tex]44.8g/eq=\frac{\text{Molar mass}}{2eq/mol}\\\\\text{Molar mass}=(44.8g/eq\times 2eq/mol)=89.6g/mol[/tex]
Hence, the molecular weight of the dibasic acid is 89.6 g/mol
