CBSE 2023 · Region 2 · Set 2 · Q20 · 2 marks
The vapour pressure of pure liquid X and pure liquid Y at $\displaystyle 25$ °C are $\displaystyle 120$ mm Hg and $\displaystyle 160$ mm Hg respectively. If equal moles of X and Y are mixed to form an ideal solution, calculate the vapour pressure of the solution.
Marking-scheme solution
\[\begin{aligned}
\mathrm{P}_{\text {Total }} & =\mathrm{p}^{\circ}{ }_{\mathrm{X}} \chi_{\mathrm{X}}+\mathrm{p}^{\circ}{ }_{\mathrm{Y}} \chi_{\mathrm{B}} \\
\chi_{\mathrm{X}} & =\chi_{\mathrm{B}}=0.5 \\
\mathrm{P}_{\text {Total }} & =(120 \times 0.5)+(160 \times 0.5) \\
& =140 \mathrm{~mm} \mathrm{Hg}
\end{aligned}
\]
SolutionsVapour Pressure of Liquid SolutionsApplyvery_short_answereasy
More from Solutions
- 0.3 g of acetic acid (M=60 g mol^-1) dissolved in 30 g of benzene shows a depression in freezing point equal…2023 · asked 6×
- Define molal depression constant. How is it related to enthalpy of fusion? OR What type of deviation is shown…2024 · asked 3×
- When a liquid and its vapour are at equilibrium and the pressure is suddenly decreased:2026 · asked 3×
- Shweta mixed two liquids A and B of 10 mL each. After mixing, the volume of the solution was found to be 20 ·…2025 · asked 3×
- Explain the following with the help of Henry's law: (i) Bends (ii) Anoxia OR How does sprinkling of salt help…2026 · asked 3×
- Calculate the vapour pressure of a solution containing 61 g of benzoic acid (molar mass =122 g mol^-1 )…2026 · asked 3×
- The boiling point of one molal NaCl solution, assuming NaCl to be completely dissociated in water is: (K b.…2026 · asked 3×
- Give reasons: Cooking is faster in pressure cooker than in an open pan. On mixing liquid X and liquid Y,…2025 · asked 3×
CBSE Class 12 Chemistry past-paper question from the 2023board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.