$C_{6}H_{6}$ freezes at $5.5^{\circ} C$. The temperature at which a solution of $10 \ g$ of $C_{4}H_{10}$ in $200 \ g$ of $C_{6}H_{6}$ freezes is $...... \ ^{\circ} C$. (The molal freezing point depression constant of $C_{6}H_{6}$ is $5.12 \ ^{\circ} C/m$.)

$2.7 \ kg$ of each of water and acetic acid are mixed. The freezing point of the solution will be $-x^{\circ} C$. Consider the acetic acid does not dimerise in water,nor dissociates in water. $x = . . . . . . .$ (nearest integer)
[Given : Molar mass of water $= 18 \ g \ mol^{-1}$,acetic acid $= 60 \ g \ mol^{-1}$]
$K_f \ H_2O = 1.86 \ K \ kg \ mol^{-1}$
$K_f$ acetic acid $= 3.90 \ K \ kg \ mol^{-1}$
Freezing point: $H_2O = 273 \ K$,acetic acid $= 290 \ K$

$A$ $5\%$ 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 ............. $K$.

What is observed during the depression of freezing point?

Under identical conditions,which aqueous solutions have the same freezing point? (Molecular mass of urea $= 60 \ u$ and glucose $= 180 \ u$)

Calculate the molar mass of a nonvolatile solute when $1.5 \ g$ of it is dissolved in $90 \ g$ of solvent,decreasing its freezing point by $0.25 \ K$. Given: $K_{f} = 1.2 \ K \ kg \ mol^{-1}$.