Understanding Molar Volume at STP

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One mole of any gas occupies 22.4 L at standard temperature and pressure (STP), defined as 0°C and 1 atm. If the volume of the container is increased, the pressure will change, indicating that the conditions are no longer at STP. In an isolated system, expansion can be adiabatic, affecting both temperature and pressure. However, in a closed, rigid container at STP, once equilibrium is reached with the environment, the temperature remains constant while pressure changes. Understanding these principles clarifies the relationship between volume, pressure, and temperature in gas behavior.
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Homework Statement


We know that one mole of any gas occupies 22.4 L at STP. But I am a little confused because if I increase the volume of the container then the volume will also change, but how is there a fixed value of 22.4 L?

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The Attempt at a Solution


I reasoned it out as follows : if the volume of container is changed, the standard pressure is not maintained at 1 atm , so it is no longer STP. Please correct me if i am wrong, and help me with some additional information if i am correct.[/B]
 
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subhradeep mahata said:
I reasoned it out as follows : if the volume of container is changed, the standard pressure is not maintained at 1 atm , so it is no longer STP. Please correct me if i am wrong, and help me with some additional information if i am correct.
The result will vary depending on how the volume of the container is increased, and what other conditions apply. For instance, if the container is isolated from the rest of the universe, then no additional energy can enter the container, such the expansion will be adiabatic, and both the temperature and the pressure of the gas will change.

In the case of a closed rigid container sitting on a lab bench at STP, after the change of volume and after the container has reached equilibrium with the room, then indeed you will find that pressure has changed (but not the temperature, as we have assumed that it is in equilibrium at standard T).
 
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