Question

c. given that atmospheric pressure is 760.2 mm hg, calculate the total gas pressure inside the tube pictured at right, with the water level inside the tube 7.5 cm below the surrounding water.

Explanation:

Step1: Convert the height difference unit

Since \(1\ cm = 10\ mm\), then \(7.5\ cm=75\ mm\).

Step2: Calculate the gas pressure

The pressure of the gas inside the tube \(P_{gas}\) is related to the atmospheric pressure \(P_{atm}\) by the formula \(P_{gas}=P_{atm}+P_{h}\) (where \(P_{h}\) is the pressure due to the height difference of the liquid column). Given \(P_{atm} = 760.2\ mm\ Hg\) and \(P_{h}=75\ mm\ Hg\) (assuming the liquid is water, and using the conversion for pressure - height relationship in terms of equivalent \(Hg\) - like units for simplicity in this context as we are comparing in \(mm\ Hg\) units for pressure calculation here). Then \(P_{gas}=760.2 + 75\).

Answer:

\(835.2\ mm\ Hg\)