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Karan Punjabi
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Ar STP Every gas occupies same volume of 22.4 L but how it can be because every gas molecule has different size right? So they should occupy different volumes right? If I'm wrong at any point then please correct me
In an ideal gas, the molecules are far apart. The size of molecules is a small fraction of the total volume. That is the assumption that goes into the 22.4 liters per mole approximation. In a diffuse gas, pressure is a function of the average kinetic energy of each molecule and the concentration of molecules. At STP and one mole per 22.4 liters, the average kinetic energy and the concentration of molecules is fixed and does not depend on molecular weight. Accordingly, the pressure is fixed and does not depend on molecular weight.Karan Punjabi said:Ar STP Every gas occupies same volume of 22.4 L but how it can be because every gas molecule has different size right? So they should occupy different volumes right? If I'm wrong at any point then please correct me
So that's just a approximation that volume is 22.4 L but in practical the volume vary little bit right ? I know that kinetic energy is fixed for any gas at a given constant temperature.jbriggs444 said:In an ideal gas, the molecules are far apart. The size of molecules is a small fraction of the total volume. That is the assumption that goes into the 22.4 liters per mole approximation. In a diffuse gas, pressure is a function of the average kinetic energy of each molecule and the concentration of molecules. At STP and one mole per 22.4 liters, the average kinetic energy and the concentration of molecules is fixed and does not depend on molecular weight. Accordingly, the pressure is fixed and does not depend on molecular weight.
Right. Real gasses are not quite ideal.Karan Punjabi said:So that's just a approximation that volume is 22.4 L but in practical the volume vary little bit right ? I know that kinetic energy is fixed for any gas at a given constant temperature.
Thank you so much this doubt was not letting me study for my exams.jbriggs444 said:Right. Real gasses are not quite ideal.
The size of a molecule has a direct impact on the volume it occupies. In general, smaller molecules have a smaller occupied volume compared to larger molecules. This is because smaller molecules have less surface area, allowing them to pack more closely together and take up less space.
The size of a gas molecule can affect its behavior in several ways. Smaller molecules tend to have lower boiling points and are more likely to be gases at room temperature. They also have a higher diffusion rate, meaning they can spread and mix more quickly with other gases. Larger molecules, on the other hand, are more likely to be liquids or solids at room temperature and have a slower diffusion rate.
Yes, two gases with different molecule sizes can occupy the same volume. This is because gases are made up of individual particles that are spaced far apart, allowing them to move and mix freely. As long as the total number of particles is the same, the gases can occupy the same volume.
Intermolecular forces, such as London dispersion forces and hydrogen bonding, can affect the occupied volume of gases. These forces can cause gas molecules to attract and stick together, reducing the overall volume they occupy. This is why gases with stronger intermolecular forces, such as water vapor, tend to have a smaller occupied volume compared to gases with weaker intermolecular forces, such as hydrogen gas.
There is no definite limit to how small a gas molecule can be. However, smaller molecules may exhibit different properties and behaviors compared to larger molecules. At extremely small sizes, quantum effects may also come into play, causing gases to behave differently than classical gases.