The molality of the toluene is 1.46 mol/kg.
The molality of a solution is its molal concentration. Molal concentration is denoted by m. It is the mol of solute dissolves in 1 Kg solvent.
The depression at freezing point is directly proportional to the molality of the solution. The equation we use for this type of problem is:
ΔT=iKm [tex]f_m[/tex]
Where, ΔT [tex]f_m[/tex] is depression at freezing point, i is Van't hoff factor, m is molality and [tex]K_f[/tex] is the freezing point depression constant.
Toluene is a non-electrolyte and so the value of i for this is 1.
Depression at a freezing point is given as -13.[tex]0^0[/tex] and the [tex]K_f[/tex] is given as 5.12. So, we could calculate the molality of the solution using the equation written above.
Let's plug in the values in the equation:
ΔT=iKm[tex]f_m[/tex]
-7.51 =1 x5. 12 xm
m = [tex]\frac{7.51}{5. 12}[/tex]
m = 1.46 m
It means the molality of the solution is 1.46 mol/kg.
Hence, the molality of the solution is 1.46 mol/kg.
Learn more about the molality of the solution here:
https://brainly.com/question/12123356
#SPJ1