What is the weight in pounds-force (lbf) of one gallon of air at standard atmospheric pressure (1 atm) and a temperature of 25°C? Assume the molar mass of air is 28.97 g/mol (0.02897 kg/mol).

Mechanical Engineering Mcqs for PPSC, FPSC, NTS, and Pakistan government job tests. Select an option below, then read the explanation.

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Mechanical Engineering Mcqsmechanical-engineering-mcqs
Published
1 Feb 2022
Last updated
28 May 2026

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Explanation

The weight of one gallon of air under the given conditions is approximately 0.00989 lbf. This is calculated by applying the ideal gas law to find the mass of air in one gallon and then converting that mass to weight in pounds-force at standard gravity.

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