Answer to Question #307238 in General Chemistry for Syd Hernan

Question

The molal freezing point of water is 1.86ºC/m (1.86K/m), which can be expressed as 1.86ºC ● kg H2O/mol solute (1.86K ● kg H2O/mol solute) after some algebraic rearrangement. This means that a solution of 1 mol cane sugar (342g, over 3 4 lb) dissolved in 1kg of water should freeze at -1.86ºC.

Describe the freezing point drop suggests in number 1.

Answer 1

The solution has a lower freezing point than pure solvent. The solute solvent interaction prevent the solvent from going into solid phase. Therefore lowering the freezing point.