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Chemistry · PYQ NEET UG 2021
हिन्दीThe CORRECT option for the value of vapour pressure of a solution at \( 45\text{ }^\circ\text{C} \) with benzene to octane in molar ratio 3:2 is _______. [At \( 45\text{ }^\circ\text{C} \) vapour pressure of benzene is \( 280\text{ mm of Hg} \) and that of octane is \( 420\text{ mm of Hg} \). Assume ideal gas]
Correct answer · Option B
\( 336\text{ mm of Hg} \)
Explanation
Using Raoult's Law: \( P_{\text{total}} = x_B P_B^\circ + x_O P_O^\circ = (\frac{3}{5})\times 280 + (\frac{2}{5})\times 420 = 168 + 168 = 336\text{ mm of Hg} \).
