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On mixing, heptane and octane form an ideal solution. At 373 ~K, the vapour pressures of the two liquid components (heptane and octane) are 105 kPa…

JEE Main 2010 — Chemistry Physical Chemistry

2010mcqmedium

On mixing, heptane and octane form an ideal solution. At 373 K373 \mathrm{~K}373 K, the vapour pressures of the two liquid components (heptane and octane) are 105kPa105 \mathrm{kPa}105kPa and 45kPa45 \mathrm{kPa}45kPa respectively. Vapour pressure of the solution obtained by mixing 25.0 g25.0 \mathrm{~g}25.0 g of heptane and 35 g35 \mathrm{~g}35 g of octane will be (molar mass of heptane =100 g mol−1=100 \mathrm{~g} \mathrm{~mol}^{-1}=100 g mol−1 an dof octane =114 g mol−1=114 \mathrm{~g} \mathrm{~mol}^{-1}=114 g mol−1 ).

Official previous-year question

Held on 30 Apr 2010 · Verified 6 Jul 2026.

Options

  1. A

    72.0kPa72.0 \mathrm{kPa}72.0kPa

  2. B

    36.1kPa36.1 \mathrm{kPa}36.1kPa

  3. C

    96.2kPa96.2 \mathrm{kPa}96.2kPa

  4. D

    144.5kPa144.5 \mathrm{kPa}144.5kPa

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