Respuesta :
Explanation:
It is known that molar mass of [tex]SO^{2-}_{4}[/tex] is as follows.
Molar mass = [tex]32 + (4 \times 16)[/tex]
= 96 g/mol
It is given that the concentration of [tex]SO^{2-}_{4}[/tex] is 1.5 g/L.
(a) As 96 g of [tex]SO^{2-}_{4}[/tex] contains 32 grams of Sulfur in 1 L. And, 1.5 g of [tex]SO^{2-}_{4}[/tex] contains x grams of sulfur in 1 L.
Therefore, value of x is calculated as follows.
x = [tex]\frac{1.5 \times 32}{96}[/tex]
= 0.5 g/L
Hence, the concentration of sulfur is 0.5 g/L.
(b) Now, calculate the molar concentration of sulfur as follows.
Molarity = [tex]\frac{\text{conc. of sulfate}}{\text{molar mass of SO^{2-}_{4}}}[/tex]
= [tex]\frac{1.5 g/L}{96 g/mol}[/tex]
= 0.0156 M
Therefore, the molarity of given sample is 0.0156 M.
(c) Calculate the normality as follows.
Equivalent mass of [tex]SO^{2-}_{4}[/tex] = [tex]\frac{96}{2}[/tex]
= 48 g/mol
Normality = [tex] \frac{conc. of SO^{2-}_{4} in g/L}{equivalent mass of SO^{2-}_{4}}[/tex]
= [tex]\frac{1.5 g/L}{48 g/mol}[/tex]
= 0.03125 N
Hence, the normality of given sample is 0.03125 N.
