What is the molal concentration of a sucrose (C12H22011) solution whose freezing point is
-2.00 °C? The Kf for water is 1.86 °C/m.

Respuesta :

Answer: The molal concentration of sucrose solution is 1.07 m

Explanation:

Depression in freezing point is given by:

[tex]\Delta T_f=i\times K_f\times m[/tex]

[tex]\Delta T_f=T_f^0-T_f=0.00-(-2.00)^0C=2.00^0C[/tex] = Depression in freezing point

i= vant hoff factor = 1 (for non electrolyte such as sucrose)

[tex]K_f[/tex] = freezing point constant = [tex]1.86^0C/m[/tex]

m= molality

Putting in the values:

[tex]2.00^0C=1\times 1.86^0C/m\times m[/tex]

[tex]m=1.07[/tex]

Thus molal concentration of sucrose solution is 1.07 m