Isothermal Expansions

[Megan Mitchell 2B]

In the textbook example of an isothermal expansion, it shows heat being added to the cylinder. How does the gas stay at the same temperature if heat is added? Does it cool down as it expands?

[Navdeep Kaur 2F]

An isothermal expansion is when the temperature is always constant. Even when putting in heat, the temp is constant because heat is also being released through work.

[Peter_Wisner_3F]

The gas is able to stay at the same temperature because the heat is converted into work instead.

[Gregory_Kislik_2C]

Yes, a gas cools down as it expands. A way to think about heat transfer is that it is related to the number of collisions between molecules. When a gas expands, there are fewer collisions because molecules are farther apart, meaning that internal energy goes down. In order for the internal energy to stay the same and the reaction to be isothermic, heat needs to be added so that temperature does not decrease. I hope this helps, please let me know if there are any errors.

[Matthew Do 2G]

Yes, the gas does constantly cool down as it is undergoing isothermal expansions. However, to compensate for this loss of energy, more heat is added to the system which allows the gas to stay at a constant temperature, making it isothermal throughout the beginning and the end of the reaction.

[Yixin Wu 3B]

Yes, isothermal expansion means that the temperature stays constant throughout the process, which indicates that the heat is converted to other forms of energy. In this case, the heat energy is converted to do work on the system for expansion.

[Jonathan Choe 3D]

An isothermal expansion is when the temperature is constant. The temperature is constant even when adding heat since heat is also being released through work.

[Tamara Andrijanic 1L]

Yes, since temperature is just the avg KE of particle collisions, it will stay constant with the heat added to the system