Camphor (C10H16O) has a normal melting point of 179.8 oC, with a molal freezing point depression...

Camphor (C10H16O) has a normal melting point of 179.8 oC, with a molal freezing point depression constant of 40.0 oC/m. When 224.0 mg of an unknown organic material was dissolved in 26.74 g of pure camphor, the freezing point of the solution (P = 1 atm) was 174.5 oC. What is the molar mass (g/mol) of the material? ΔTf = iKfm.

a) 45.31 b) 194.2 c) 223.4 d) 96.42 e) 135.2 f) 63.22

Expert Solution

Note: There is no information about the vant Hoff factor 'i' in the given question, so, we consider it to be i = 1,which means solute do not dissociate in solution. Further, we used C as the molal concentration variable instead of 'm' to avoid the confusion of 'm' as the unit symbol of molality.

queen_honey_blossom answered 2 years ago

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