Chapter 14 - Thermal Physics Flashcards
What is the triple point of a substance?
The triple point of a substance is where the three states of matter (solid, liquid and gas) of the substance can exist in thermal equilibrium ie. there is no net transfer of thermal energy between the phases.
What is the unit for temperature?
Kelvin.
What direction is the net flow of thermal energy?
From the object with higher temperature to lower temperature.
What happens when two objects are in thermal equilibrium (same temperature)?
There is no net flow of thermal energy between them.
When will thermal energy transfer always occur?
When there exists an energy difference between two points/media.
What is the Zeroth Law of Thermodynamics?
“If two bodies A and B are in thermal equilibrium with third body C, then body A and B are also in thermal equilibrium with each other”
What is the First Law of Thermodynamics?
“The net change in total energy of a system (∆E) is equal to the heat added to the system (Q) minus work done by the system (W)”
What is the Second Law of Thermodynamics?
“In all the spontaneous processes, the entropy of the universe increases”
What is the Third Law of Thermodynamics?
“The value of entropy of a completely pure crystalline substance is zero at absolute zero temperature”
What are the two temperature scales?
