A volume of 20 ml of ethane gas is mixed with 78 ml oxygen gas in an eudiometer tube at 30°C and fired. When the resulting gases are cooled to 30°C, the volume of eudiometer becomes 50 ml. What is the

Question

A volume of 20 ml of ethane gas is mixed with 78 ml oxygen gas in an eudiometer tube at 30°C and fired. When the resulting gases are cooled to 30°C, the volume of eudiometer becomes 50 ml. What is the vapour pressure of water at 30°C? Neglect the volume occupied by liquid water. Pressure is 1 atm and constant throughout.

TestHub · Accepted Answer

2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O. 20 ml C₂H₆ consumes 70 ml O₂ and gives 40 ml CO₂; O₂ left = 8 ml. Dry gases = 40 + 8 = 48 ml (at 1 atm equivalent). In the final 50 ml the dry gases exert 48/50 atm, so p(H₂O) = 2/50 atm = 0.04 atm = 30.4 mm Hg. Confirms Ans: (b) 30.4 mm Hg.

Chemistry - Ideal Gas Question with Solution | TestHub

Options:

Doubts & Discussion