Question

What is the pressure in a gas container that is connected to an closed-end U-tube manometer if the pressure of the atmosphere is 742 torr and the level of mercury in the arm connected to the container is 8.60 cm higher than the level of mercury open to the atmosphere?A) 656 mm HgB) 8.60 mm HgC) 751 mm HgD) 860 mm Hg

Answer 1

Answer: A) 656 mm Hg

Explanation:

Pressure of the gas is defined as the force exerted by the particles on the walls of the container. It is expressed in various terms like 'mmHg', 'atm', 'kiloPascals' etc..

All these units of pressure are inter convertible.

We are given:

Pressure of the atmosphere = 742 torr = 742 mm Hg (1mmHg = 1 torr)

Pressure of mercury = 8.60 cm = 86.0 mm Hg  (1cm = 10 mm)

Thus pressure of the gas container = Pressure of the atmosphere - Pressure of mercury = (742 - 86.0) mm Hg= 656 mm Hg

Thus the pressure in a gas container that is connected to an closed-end U-tube manometer is 656 mm Hg.