To determine the freezing point we can apply the following formula that relates the molality to the freezing point of water:
![\Delta T_f=K_f* m](https://img.qammunity.org/2023/formulas/chemistry/college/zinabqxnt8baq950xyafgizjp6qoj3ux0p.png)
Where,
m is the molality
Kf is the freezing point of water
DeltaTf= Freezing point
We replace the known data:
![\Delta T_f=1.86(\degree C)/(m)*0.800m=1.49\degree C](https://img.qammunity.org/2023/formulas/chemistry/college/nj8yl7p100d7omklrcbue9qiqk71kc35nj.png)
So, the freezing point of the solution will be 1.49°C