Answer:
101.260 ° C
Explanation:
From the given information;
The molarity of lactose solution (m) can be calculated as:
[tex]m = \dfrac{25.1 \times \dfrac{1 \ mol \ (NH_2)_2 \ CO}{60.01 g} }{0.170 \ kg }[/tex]
m = 2.46 m
The molar elevation constant of water [tex]k_b = 0.512 ^0 \ C/m[/tex]
Using the elevation in boiling point ;
i.e.
[tex]\Delta T_b = k_b \times m[/tex]
[tex]\Delta T_b = 0.512 \ ^0C/m \times 2.46 \ m[/tex]
[tex]\Delta T_b = 1.260 \ ^0C[/tex]
The boiling point of water solvent;
[tex]T_{water \ solvent} = 100^0 C[/tex]
Elevation in boiling point;
[tex]T_b = T_{solution} - T_{water \ solvent}[/tex]
[tex]T_{solution} = T_b+ T_{water \ solvent}[/tex]
[tex]T_{solution} = 1.260 \ ^0 C + 100 ^ 0 \ C[/tex]
[tex]T_{solution} = 101.260 \ ^0 C[/tex]