Answer to Question #223673 in General Chemistry for Hilma

Question

An open-end mercury manometer was connected to a flask containing a gas at unknown pressure. The mercury in the arm open to the atmospheric pressure was 76mm lower than the mercury in the arm connected to the flask. The atmospheric pressure 749 torr. What was the Pressure of the gas in the flask in Pascal?

Answer 1

If the knee of the pressure gauge were connected to the atmosphere, the mercury level in the knees would be the same. The level difference is 76 mm. Consequently, the gas pressure is 76 mm higher than the atmospheric pressure and is equal to 825,002098 mm Hg.

749 Torr is equal to 749.002098 millimeters of mercury

749.002098+76=825,002098

825.002098 millimeters of mercury is equal to 109 990.926 pascals