InterviewSolution
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InterviewSolution
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The freezing point of water is depressed by `0.37^(@)C` in a 0.01 molal NaCl solution. The freezing point of 0.02 molal solution of urea is depressed byA. `0.37^(@)C`B. `0.74^(@)C`C. `0.185^(@)C`D. `0^(@)C` |
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Answer» Correct Answer - A The depression in freezing point is proportional to molal concentration of the solute i.e. `Delta T_(f) prop m` `Delta T_(f)=K_(f)mi` or `K_(f)=(Delta T_(f))/(ixxm)` = constant so, `(Delta T_(f_(NaCl)))/(i_(NaCl)xxm_(NaCl))=(Delta T_(f_("Urea")))/(m_("Urea")xxi_("Urea"))` = constant `(0.37)/(2xx0.01)=(Delta T_(f_("Urea")))/(0.02xx1)rArr Delta T_(f_("Urea"))=(0.37xx0.02)/(0.02)=0.37^(@)C`. |
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