A flask containing a gas was connected to both a closed-end and an open-end manometer. In the closed-end manometer, the mercury in the sealed arm was 755 mm above the level in the arm connected to the fax. In the open-end manometer,the arm connected to the gas was 17 mm higher than the side open to the air. What was the atmospheric pressure in torr?
To determine the atmospheric pressure in torr, we need to use the information provided about the manometers.
In the closed-end manometer, the mercury in the sealed arm was 755 mm above the level in the arm connected to the flask. This means that the pressure inside the flask is greater than the atmospheric pressure. We can denote this pressure as P1.
In the open-end manometer, the arm connected to the gas was 17 mm higher than the side open to the air. This indicates that the pressure inside the flask is lower than the atmospheric pressure. We can denote this pressure as P2.
To find the atmospheric pressure, we can compare the two pressures P1 and P2.
First, we need to convert the difference in mercury levels to a pressure difference. Since 1 mmHg (millimeter of mercury) is equal to 1 torr, we can say that the pressure difference in the closed-end manometer is 755 torr.
Next, we need to calculate the pressure difference in the open-end manometer. The difference in mercury levels is given as 17 mm, so the pressure difference is also 17 torr.
Now, we can compare the two pressure differences:
P1 - P2 = 755 torr - 17 torr = 738 torr
Since P1 is greater than P2, we know that P1 represents the pressure inside the flask, and P2 represents the atmospheric pressure.
Therefore, the atmospheric pressure is 738 torr.