A closed container is filled with various gases; how does the molecular weight affect pressure changes?
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A closed container is filled with various gases. Question: When the same volume of gas is introduced, which one, those with a higher molecular weight or those with a lower molecular weight, will result in a greater increase in pressure? Why?
This post was last edited by he*aoyu8911 on 2017-6-22 at 17:29. Everyone’s stress should decrease, right?? First of all, for the purposes of thermodynamic calculations, the partial pressure pB of any component B in a mixed gas – whether it’s an ideal gas or a real gas – is defined as the total pressure p multiplied by its molar fraction yB; that is, pB = p yB. And yB = nB / n. For gases, the number of moles in a given volume is the same, and the total pressure equals the sum of the partial pressures. However, in practical applications there are still differences in the standard molar volume. What truly affects the partial pressure of a gas is the direct influence of its boiling point on pressure. Generally speaking, gases with lower boiling points behave more like ideal gases at higher temperatures and lower pressures. For example, the boiling point of oxygen is -183°C, while that of hydrogen is -253°C; under normal temperature and pressure, their molar volumes differ from the ideal values by only about 0.1%. In contrast, the boiling point of sulfur dioxide is -10°C, and under normal temperature and pressure its molar volume differs from the ideal value by 2.4%.
When the filled volume is the same, the increase in pressure is independent of molecular weight.
There’s nothing to say; even a little knowledge is enough to understand it