How is the binary gas diffusion coefficient D dependent on system pressure P ___________________?
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Answer: C. D ∝ 1/P
Explanation
Binary gas diffusivity is inversely proportional to total system pressure based on kinetic theory derivations. Doubling the operating pressure cuts the binary gas diffusion coefficient exactly in half due to increased crowding. This well validated inverse relationship holds true for most moderate pressure gas phase mixtures. Gas molecules travel shorter distances between collisions when the total system pressure is elevated. Transport properties in gases depend strongly on density and temperature rather than chemical complexity alone. Empirical correlations confirm that molecular diffusion slows down proportionally as system pressure increases.
Designing industrial gas separation units requires accurate accounting of pressure effects on diffusion rates. Chemical engineers use pressure correction factors when scaling pilot plant absorption towers to commercial sizes. Understanding pressure dependence helps optimize operating conditions in high throughput catalytic reactors. Fractional power dependencies of pressure do not match the fundamental molecular collision models of gases. Inverse square root pressure scaling incorrectly calculates the density impact on binary molecular diffusion. Higher order pressure dependencies exaggerate the slowdown of molecular transport in moderate pressure systems.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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