A solution of sucrose (molar mass $=\mathrm{342 }\mathrm{g}\mathrm{m}\mathrm{o}{\mathrm{l}}^{-1}$ ) has been prepared by dissolving 68.5 g of sucrose in 1000 g of water. The freezing point of the solution obtained will be
( ${\mathrm{K}}_{\mathrm{f}}$ for water $=\mathrm{1.86 }\mathrm{K}\mathrm{k}\mathrm{g}\mathrm{m}\mathrm{o}{\mathrm{l}}^{-1}$ )