An aqueous solution of a non-volatile solute freezes at , while pure water freezes at . Determine…

An aqueous solution of a non-volatile solute freezes at $272\cdot4\text{ K}$, while pure water freezes at $273\cdot0\text{ K}$. Determine the following: (Given $K_f = 1\cdot86\text{ K kg mol}^{-1}$, $K_b = 0\cdot512\text{ K kg mol}^{-1}$ and vapour pressure of water at $298\text{ K} = 23\cdot756\text{ mm of Hg}$) (1) The molality of solution (2) Boiling point of solution (3) The lowering of vapour pressure of water at $298\text{ K}$

A solution containing $1\cdot23\text{ g}$ of calcium nitrate in $10\text{ g}$ of water, boils at $100\cdot975^\circ\text{C}$ at $760\text{ mm of Hg}$. Calculate the van’t Hoff factor for the salt at this concentration. ($K_b$ for water $= 0\cdot52\text{ K kg mol}^{-1}$, mol. wt. of calcium nitrate $= 164\text{ g mol}^{-1}$)