Question

3. A vessel contains a mixture of equal weights of
oxygen and SO, at a pressure of 600mm of Hg.
The partial pressure of oxygen in mm is
1) 200
2) 300
4) 100
3) 400​

Answer 1

Answer:

Answer 2 is correct

Explanation:

According to Raoult law partial pressure is product of mole fraction and total pressure

According to law of partial pressure,

n of O2

Partial pressure of O2 = ---------------------. X Total P

n of O2+ nof SO

(where n is moles)

Answer 2

The partial pressure of oxygen in a vessel containing a mixture of oxygen and SO2, at a pressure of 600 mm of Hg is equal to 400 mm of Hg.

• The molar mass of O2 and SO2 are 32 and 64 respectively.
• So a mixture containing equal weights of the two will have moles of oxygen double of the moles of SO2.
• Hence, mole fraction of O2 is 2/3.
• Now, according to dalton's law of partial pressure, the partial pressure is equal to the product of the total pressure and the mole fraction.
• Therefore, the partial pressure of oxygen is equal to 400 mm of Hg (600×2/3).