What happens to temperature during phase change?
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What happens to temperature during phase change?
I'm confused about what happens to the temperature of a reactant, lets say water, during its phase change from a liquid to a gas. Does the temperature increase as more energy is applied to it during the phase change? How would this work when you would go to calculate the total bond enthalpy of a reaction when there is a phase change within it?
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Re: What happens to temperature during phase change?
During phase changes, the temperature does not change as the energy applied to the reaction is fully put toward causing the phase change. To calculate the total enthalpy, you can add the enthalpy of the bonds to the enthalpy of the phase change (which is usually given).
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Re: What happens to temperature during phase change?
Based on what I heard during lecture, because heat is required during a phase change, the temperature of the sample remains constant even though heat is being supplied.
Re: What happens to temperature during phase change?
A good way to visualize the the changes in temperature/energy is by looking at a phase change graph. The phase changes occur where the graph is a horizontal line, which demonstrates that there is no temperature change, even though the heat energy is increasing. So this shows that there's no temp change during a phase change.
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Re: What happens to temperature during phase change?
The temperature remains stagnant during the phase change, as the energy is used to affect the bonds instead of fueling the kinetic movement of molecules (which temperature basically measures).
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Re: What happens to temperature during phase change?
Based on my understanding, the temperature would increase as heat is supplied generally, though when there is a plateau in the graph heat supply will not have an influence until it is high enough to induce a phase change.
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Re: What happens to temperature during phase change?
During a phase change, there would be no change in temperature. A very helpful graph in lecture shows how temperature remains constant (horizontal line) during the phase change process. It is important to note that heat does not equal temperature, so although heat is applied, the temperature is fixed for that period of time (phase change).
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Re: What happens to temperature during phase change?
During the actual phase change, there is no change in temperature.
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Re: What happens to temperature during phase change?
During a phase change, the temperature does not change because the energy put into the system is used completely during the phase transitions. To go through a phase transition like liquid to vapor, the bonds have to be broken. Heat is going to break the bonds for the phase change to occur, causing the temperature to stay constant.
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Re: What happens to temperature during phase change?
During a phase change, the temperature remains constant as all incoming energy is redirected into changing the state of the object. For example, as water is being changed from a liquid to a gas, the liquid will remain at 100 degrees Celsius while it is being converted into a gas, then the gas particles may be heated past that 100 degree mark.
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Re: What happens to temperature during phase change?
Hi! During the phase change the temperature doesn't change. This is because the heat is being used for transitioning the change of phase (for example breaking bonds) so the temperature would stay the same.
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Re: What happens to temperature during phase change?
I believe that the temperature would remain constant during phase change since the energy is used for breaking the molecules in phase change.
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Re: What happens to temperature during phase change?
There will be no change in temperature since the heat will be used during the change of phase.
Re: What happens to temperature during phase change?
The temperature does not change during a phase change because the heat is used during the process of phase changing so the temperature will stay the same.
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Re: What happens to temperature during phase change?
During phase changes, the temperature of a substance remains constant because the energy is not used to increase the kinetic energy of the molecules (aka the temperature) but is used to break the bonds for the phase change to occur.
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Re: What happens to temperature during phase change?
During a phase change, the temperature does not increase because it is being used to break the bonds in order to induce the phase change. Since it's focused on breaking intermolecular bonds of the molecule, the overall net heat is not increasing. To calculate the bond enthalpy, you add the enthalpies of the individual bonds(given). For each bond in the molecule, you must account for it being broken.
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Re: What happens to temperature during phase change?
The temperature of a substance remains constant while a phase change occurs. Endothermic processes go from low energy to high energy: solid to liquid to gas.
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