You have an-empty 42-gatbarrel-and-a 10-lb bag of dry alum, Al2(SO4). (a) Calculate the number of gallons of 0.05 M solution you can make with this amount of alumthe-materials you hve on hand. (b) Suppose you put all the alum into a 42-gal-the barrel and filled it full Calculate the molar concentration of the resulting solution

Respuesta :

Answer:

a) 70.074 of gallons of 0.05 M solution we can make.

b) 0.0834 M is the molar concentration of the resulting solution.

Explanation:

Concentration of alum solution = c

Moles of alum  in solution = n

Volume of solution = V

[tex]c=\frac{n}{V(L)}[/tex]

a) Mass of alum = 10 lbs = 4535.92 g

(1 lb = 453.592 g )

Molar mass of alum[tex]Al_2(SO_4)_3 = 342 g/mol[/tex]

Moles of alum = [tex]\frac{4535.92 g}{342 g/mol}=13.263 mol[/tex]

Volume of alum solution of 0.05 m = V

[tex]0.05M=\frac{13.263 mol}{V}[/tex]

[tex]V=\frac{13.263 mol}{0.05 M}=265.26 L = 70.074 gallons[/tex]

(1 L = 0.264172 gallons)

70.074 of gallons of 0.05 M solution we can make.

b) Moles of alum = [tex]\frac{4535.92 g}{342 g/mol}=13.263 mol[/tex]

Volume of the barrel = 42 gallons  = 158.99 L

Concentration of alum : C

[tex]C=\frac{13.263 mol}{158.99 L}=0.0834 mol/L=0.0834 M[/tex]

0.0834 M is the molar concentration of the resulting solution.