The molal elevation constant of water is 0.512C/m,therefore boiling point of 0.1m CaCl2 solution in water is expected to be

Addition of a solute increases the boiling point of solvent. which is given by the formula,

                         ΔTb = i Kb
             where,            i = Van't Hoff factor
                                    ΔTb = the amount by which the boiling point is raised 
                                    m = molality (moles solute particles per kg of solution) 
                                    Kb = molal boiling-point elevation constant (solvent dependent)

Since, CaCl2 is an electrolyte, so its Van't Hoff factor will be 3 ( CaCl2 ⇋ Ca2+ + 2Cl)


Therefore, ΔTb = 3 × 0.512 oC m-1 × 0.1 m
                         = 0.1536 o

Hence the new boiling point of water will be 100 
oC + 0.1536 oC = 100.1536 oC

 

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