What happens to the freezing point of benzene when a small quantity of naphthalene is added to it?

Which of the following will show maximum depression in freezing point when the concentration is $0.1 \ M$?

If molality of the dilute solution is doubled,the value of molal depression constant $(K_f)$ will be

During the depression of freezing point in a solution,which of the following are in equilibrium?

If the freezing point of an aqueous urea solution is $271.14 \ K$ at $1 \ \text{atm}$ pressure (given $K_f$ of water = $1.86 \ K \ kg/mol$),then what is the mole fraction of urea in this solution? (Freezing point of pure water is $273 \ K$)

$A$ $5\%$ solution (by mass) of cane sugar in water has a freezing point of $271 \ K$ and the freezing point of pure water is $273.15 \ K$. The freezing point of a $5\%$ solution (by mass) of glucose in water is ............. $K$.