Understanding Molar Volume at STP

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In summary, at STP, one mole of any gas occupies 22.4 L. However, if the volume of the container is changed, the standard pressure of 1 atm is no longer maintained and the volume will also change. The result will vary depending on the conditions and changes in pressure and temperature may occur.
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subhradeep mahata
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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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Thanks sir.
 

1. What is molar volume at STP?

Molar volume at STP refers to the volume occupied by one mole of a gas at standard temperature (0°C or 273.15 K) and pressure (1 atmosphere or 101.325 kPa).

2. Why is molar volume at STP important?

Molar volume at STP is important because it allows us to easily convert between the number of moles of a gas and its volume. This is useful in various applications, such as in determining the mass of a gas or calculating the volume of a gas produced in a chemical reaction.

3. How is molar volume at STP calculated?

Molar volume at STP can be calculated by dividing the molar mass of the gas by its density at STP. Alternatively, it can also be calculated using the ideal gas law equation, V = nRT, where V is volume, n is number of moles, R is the ideal gas constant, and T is temperature in Kelvin.

4. What is the molar volume of an ideal gas at STP?

The molar volume of an ideal gas at STP is approximately 22.4 L/mol. This value is derived from the ideal gas law equation, using a value of 0.0821 L·atm/mol·K for the ideal gas constant and a temperature of 273.15 K.

5. Can molar volume at STP change?

No, molar volume at STP is a constant value for a specific gas. However, the molar volume can vary for different gases since it is dependent on the molar mass and density of the gas.

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