Question

A solution of propylene glycol (antifreeze) in the car's radiator has a freezing point of -20°C. What is the molality of the solution?

Answer 1

$\Delta T=Km$

K-constant (1.86°C)

$\Delta T=0-(-20)=20$ , frizzing temperature of pure water is 0

$m=20/1.86=10.75$