Most Important Selected Qs for JEE AdvancedChemistrySolutions
Paragraph: Colligative properties are very important properties of the solution. These properties are based on amount of solute and solvent only. They do not depend upon the identity of the particles. The vapour pressures of pure ethanol and pure methanol are 44 mmHg and 88 mmHg at a certain temperature T ( K ) . They form an ideal solution Paragraph: Choose the incorrect option among following
Options
- AAbove graph correctly represents the variation of vapour pressure with mole fraction for an ideal solution
- BIf a non-volatile solute is added to pure methanol then only line AD appears in above graph
- CAt point F, P_M^o P_E^o = n_E n_M ( n represents moles in solution)
- DIf mole fraction of each is 0.5 , then vapor pressure of solution is 0.087 atm
Correct answer
B. If a non-volatile solute is added to pure methanol then only line AD appears in above graph
Step-by-step solution
At point F aligned & P_M=P_E & P_M^ X_M=P_E^ X_E & P_M^ n_M (n_M+n_E ) = P_E^ n_E (n_M+n_E ) & P_M^ P_E^ = n_E n_M aligned Total pressure at 0.5 mole fraction of each P_T=(44 0.5)+(88 0.5) aligned & =66 ~mm Hg & = 66 760 =0.087 ~atm aligned