A 60.0 mL60.0 mL aliquot of a 1.80 M1.80 M solution is diluted to a total volume of 218 mL.218 mL. A 109 mL109 mL portion of that solution is diluted by adding 107 mL107 mL of water. What is the final concentration? Assume the volumes are additive

Respuesta :

Answer:

The final concentration is 0.2497 M.

Explanation:

1. Molarity of the starting solution = [tex]M_1=1.80 M[/tex]

Volume of the starting solution = [tex]V_1=60.0 mL[/tex]

After dilution of the solution to 219 mL.

Molarity of solution after dilution = [tex]M_2[/tex]

Volume of the new solution = [tex]V_2=218 mL[/tex]

[tex]M_1\times V_1=M_2\times V_2[/tex] (Dilution law)

[tex]M_2=\frac{1.80 M\times 60.0 mL}{218 mL}=0.495 M[/tex]

2. Now,109 mL of 0.495 M solution was diluted by 107 mL

Molarity of the solution = [tex]M_1=0.495 M[/tex]

Volume of the solution = [tex]V_1=109 mL[/tex]

Molarity of solution after dilution = [tex]M_2[/tex]

Volume of the new solution(107 mL of water is added)  = [tex]V_2=109 mL+107 mL = 216 mL[/tex]

[tex]M_1\times V_1=M_2\times V_2[/tex] (Dilution law)

[tex]M_2=\frac{0.495 M\times 109 mL}{216 mL}=0.2497 M[/tex]

The final concentration is 0.2497 M.