Phase Changes and Heat
Moderators: Chem_Mod, Chem_Admin
-
- Posts: 121
- Joined: Fri Sep 24, 2021 6:07 am
-
- Posts: 51
- Joined: Sun Feb 28, 2021 12:15 am
Re: Phase Changes and Heat
I believe it's because the energy that would normally contribute to the rise in temperature is being used to break the bonds necessary for the phase change. I'm not quite sure though.
-
- Posts: 103
- Joined: Fri Sep 24, 2021 7:06 am
Re: Phase Changes and Heat
I believe the previous answer follows what Dr. Lavelle said in lecture, the extra energy being put into the system is going into breaking the bonds required for a phase change, not into increasing the kinetic energies of the particles, which results in no temperature increase.
-
- Posts: 109
- Joined: Fri Sep 24, 2021 5:15 am
Re: Phase Changes and Heat
During a phase change, the supplied energy is not used to increase the kinetic energy of the molecules, but to change the binding energies. Therefore, the temperature remains constant.
-
- Posts: 59
- Joined: Mon Jan 03, 2022 9:28 pm
Re: Phase Changes and Heat
Temperature doesn't change during a phase change because the added heat is used to increase the kinetic energy of molecules. Any heat beyond what is necessary to excite the molecules into a different phase would be in excess, and that is when temperature starts to increase.
-
- Posts: 101
- Joined: Fri Sep 24, 2021 5:27 am
Re: Phase Changes and Heat
Temperature doesn't rise during a phase change because instead of energy increasing the kinetic motion/vibration of the atoms in whatever material you're changing the phase of, the energy is going into breaking certain bonds so that the phase can change at all. So liquid water being raised to a boil on a molecular level will see its molecules vibrate more vigorously as it approaches its boiling point. However, when that liquid water has reached its boiling point, on the molecular level the vibration will remain constant, but bonds will begin to break in order for the liquid water to turn into water vapor.
-
- Posts: 43
- Joined: Mon Jan 03, 2022 8:38 pm
Re: Phase Changes and Heat
During a phase change, the energy given by temperature is channeled into the intermolecular forces between molecules. This is necessary, as the breaking of bonds between molecules is what causes a molecules phase to change. Once this process is finished, however, the energy is re-channeled into increasing the temperature of the environment.
-
- Posts: 52
- Joined: Mon Jan 03, 2022 9:20 pm
Re: Phase Changes and Heat
when energy is added to a system it is used to do work such as break bonds and the rest is released as heat. during phase changes the heat is primarily used to break bonds and form bonds in the substance and as a result, not much energy is left to be released as heat which means the temperature does not change during that transitional period.
-
- Posts: 50
- Joined: Fri Sep 24, 2021 7:15 am
Re: Phase Changes and Heat
The energy going into the system is being used to break the chemical bonds of molecules involved, so it does not contribute to increase in the temperature of the system.
-
- Posts: 107
- Joined: Fri Sep 24, 2021 5:12 am
-
- Posts: 25
- Joined: Mon Jan 03, 2022 8:54 pm
Re: Phase Changes and Heat
Any and all energy that is being introduced into a system that is undergoing a change in phase is devoted to breaking the bonds between the molecules in that state. Upon gaining more energy, particles can break free of intermolecular forces of attraction and undergo a change of state.
-
- Posts: 104
- Joined: Fri Sep 24, 2021 6:40 am
- Been upvoted: 1 time
Re: Phase Changes and Heat
Similar to what everyone has stated before, since the energy being added is being used to alter the structure binding state, increased energy does not contribute to increased temperature change.
Return to “Phase Changes & Related Calculations”
Who is online
Users browsing this forum: No registered users and 7 guests