Question

An open-end manometer containing mercury is connected to a container of gas, as depicted in Sample Exercise 10.2 in the book. What is the pressure of the enclosed gas in torr in each of the following situations?

Part A: The mercury in the arm attached to the gas is 15.0 cm higher than in the one open to the atmosphere; atmospheric pressure is 0.975 atm.

A. 1.97 torr
B. 0.987 torr
C. 0.990 torr
D. 1.0 torr

Answer 1

For an open-end manometer, the pressure of the enclosed gas is equal to the difference in height between the two arms of the manometer plus the atmospheric pressure. In this case, the pressure of the gas is 945.0 torr.

Step-by-step explanation:

In an open-end manometer, the pressure of the enclosed gas is equal to the difference in height between the two arms of the manometer plus the atmospheric pressure.

In this case, the mercury in the arm attached to the gas is 15.0 cm higher than in the one open to the atmosphere.

To convert this height to pressure in torr, we need to know that 1 cm of mercury equals 13.6 torr.

Therefore, the pressure of the gas is 15.0 cm * 13.6 torr/cm + 0.975 atm * 760 torr/atm = 204 torr + 741.0 torr = 945.0 torr.