Question

Diethyl ether, C4H10O was a widely used anesthetic in the early days of surgery. It has a vapor pressure of 537 torr at 25 oC. A 10.00 mL sample (D = 0.708 g/mL) is placed in a sealed 0.205 L flask. What is the maximum volume in liters the flask can have if equilibrium is to be maintained between liquid and vapor?

Answer 1

Answer:

$V=3.32 L$

Explanation:

Moles in the sample:

$n=10 mL*\frac{0.708g}{mL}*\frac{1mol}{74g}$

$n=0.096mol$

Max. volume to be in equilibrium:

$V=\frac{n*R*T}{P}$

$V=\frac{0.096mol*0.082 atm*L*mol^{-1}*K^{-1}*298K}{0.707atm}$

$V=3.32 L$

If the volume is higher, the pressure will be less than the vapour pressure and the sample will be all gas and not L-V equilibrium.