Question

gas behavior
gas pressure is a measure of the collisions of the molecules with the sides of the container. a barometer is used to measure atmospheric pressure; a manometer is used to measure the pressure in a container.

1. report the gas pressures on the flask side using the manometers below.

Explanation:

Step1: Recall pressure relationship

If the liquid - level in the open - end of the manometer is the same as in the flask side, the gas pressure in the flask is equal to the atmospheric pressure. If the liquid - level in the open - end is higher, the gas pressure in the flask is higher than the atmospheric pressure, and if the liquid - level in the open - end is lower, the gas pressure in the flask is lower than the atmospheric pressure. Assume standard atmospheric pressure $P = 760\ mmHg$.

Step2: Analyze first manometer

The liquid levels in both arms of the U - tube manometer are the same. So the gas pressure in the flask $P_1=760\ mmHg$.

Step3: Analyze second manometer

The liquid level in the open - end is higher than in the flask side. The pressure difference $\Delta P = 140\ mmHg$. So the gas pressure in the flask $P_2=760 + 140=900\ mmHg$.

Step4: Analyze third manometer

The liquid level in the open - end is lower than in the flask side. The pressure difference $\Delta P = 175\ mmHg$. So the gas pressure in the flask $P_3=760-175 = 585\ mmHg$.

Answer:

The gas pressures are: 760 mmHg, 900 mmHg, 585 mmHg.