CBSE 2024 · Region 3 · Set 1 · Q17 · 2 marks
Define molal depression constant. How is it related to enthalpy of fusion?What type of deviation is shown by ethanol and acetone mixture ? Give reason. What type of azeotropic mixture is formed by that deviation?
Define molal depression constant. How is it related to enthalpy of fusion?
What type of deviation is shown by ethanol and acetone mixture ? Give reason. What type of azeotropic mixture is formed by that deviation?
Marking-scheme solution
(a)
Molal depression constant is the depression in freezing point observed in $\displaystyle 1$ molal solution./ The depression in freezing point when one mole of non.volatile solute is dissolved in $\displaystyle 1$ kg or 1000g of the solvent.
\[\mathrm{K}_{\mathrm{f}}=\frac{\mathrm{R} \times \mathrm{M}_{\text {solvent }} \times \mathrm{T}_{\mathrm{f}}^{0}}{1000 \times \Delta_{\mathrm{fus}} \mathrm{H}^{0}}
\]
SolutionsColligative Properties and Determination of Molar MassUnderstandvery_short_answermedium
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CBSE Class 12 Chemistry past-paper question from the 2024board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.