Twice as much pentane (C₅H₁₂) is mixed with hexane (C₆H₁₄) by mass. Calculate the vapour pressure of the resulting solution. The vapour pressures of pure pentane and hexane are 425 Torr and 151 Torr, respectively. Assume ideal behaviour. A) 386 Torr B) 300 Torr C) 311 Torr D) 253 Torr E) 344 Torr

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Quizplus · Accepted Answer

The vapour pressure of the solution can be calculated using Raoult's Law. First, determine the mole fraction of each component. Let the mass of pentane be 2x and hexane be x. Calculate moles: moles of pentane = 2x/72, moles of hexane = x/86. Find mole fractions and apply Raoult's Law: P_total = (mole fraction of pentane * 425 Torr) + (mole fraction of hexane * 151 Torr). This results in approximately 344 Torr.

Twice as Much Pentane (C5H12) Is Mixed with Hexane (C6H14)

Twice as Much Pentane (C₅H₁₂) Is Mixed with Hexane (C₆H₁₄)