Pure nitrobenzene freezes at 5.67 c. when 1.0g of ethanol (c2h6o) is mixed with 20.0g nitrobenzene, the freeze point drops to –0.53 c. what is the freezing-point depression constant (kf) of nitrobenzene?

The freezing-point depression constant (Kf) of nitrobenzene is

Explanation:

Depression in freezing point is given by:

= Depression in freezing point

i= vant hoff factor = 1 (for non electrolyte nitrobenzene)

= freezing point constant = ?

m= molality

Weight of solvent = 20 g = 0.02 kg

mass of solute (ethanol) = 1.0 g

Molar mass of ethanol = 46 g/mol

Thus freezing-point depression constant (Kf) of nitrobenzene is