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C6H6 freezes at 5.5°C. The temperature at which a solution of 10 g of C4H10 in 200 g of C6H6 freeze is ...........°C. |
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Answer» We have given, Freezing point of pure C6H6 = 5.5\(^\circ\) C The molal freezing point depression constant = 5.12\(^\circ\) C/m = kf \(\triangle\)Tf = Kf m Where, \(\triangle\)Tf = depression in freezing point m = molality of solution Kf = Depression constant. Number of moles of C4H10 = \(\cfrac{4g}{58}\) = 0.069 mol molality of solution = \(\cfrac{0.069}{200}\times1000\) = 0.345 m \(\therefore\) \(\triangle\)Tf = 5.12 x 0.345 = 1.77\(^\circ\) C \(\therefore\) Freezing point of solution will be = 5.5\(^\circ\) C - 1.8\(^\circ\) C = 3.7\(^\circ\) C |
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