## Chemistry and Chemical Reactivity (9th Edition)

$-5.0^{\circ}C$
In 1 kg of the solution: Mass of solute: $11\%\times1000\ g=110\ g$ Number of moles of solute: $110\ g\div46.07\ g/mol=2.39\ mol$ Molality: $2.39\ mol\div(0.89\ kg)=2.68\ m$ Freezing point depression: $\Delta T_f=K_fm=-1.86^{\circ}C/m\times2.86\ m=-4.99^{\circ}C$ Freezing point: $-5.0^{\circ}C$