Answer:
The minimum mass of ethylene glycol = 6.641 Kg
Explanation:
[tex]\Delta T_f= T_f-T_f'\\T_f'=T_f-\Delta T_f[/tex]
Where T_f = freezing point of pure solvent water, 0°C
T_f'= Freezing point of solvent after mixture
K_f = Freezing point depression constant = 1.86 °C/m
Moecular weight of ethylene glycol = 60 g/mol
Weight of ethylene glycol = 14.5 Kg= 14.5×10^3 g
molality of ethylene glycol
[tex]m = \frac{weight}{mol.wt} \times\frac{1000}{V}[/tex]
Substitute the values to calculate m
[tex]m = \frac{w}{60} \times\frac{1000}{14.5\times1000}[/tex]
by formula
[tex]0-(-14.2) =1.86\frac{w}{60} \times\frac{1000}{14.5\times1000}[/tex]
calculating we get w = 6641.93 g
Therefore, The minimum mass of ethylene glycol = 6.641 Kg
