Question

A gas is collected over the water at 25°C. The total pressure of moist gas was 735 mm of mercury. If the aqueous vapour pressure at 25°C is 23.8 mm. Then the pressure of dry gas is

• A. 760 mm
• B. 758.8 mm
• C. 710.8 mm
• D. 711.2 mm

Answer 1

Answer: (D)

711.2 mm

Answer 2

Total pressure of (P) gas = Actual pressure of gas

P_a+ aqueous vapour pressure (P_V)

Ž $P_{a} = P - P_{V} = 735 - 23.8 = 711.2mm$