Thermal Dynamics Flashcards
Define heating
The transfer of energy from a region of higher temperature to one at a lower temperature.
Define Thermal Equilibrium
A state in which there is no net flow of thermal energy between two systems.
Define the triple point
A specific temperature and pressure where the three phases of matter can exist in thermal equilibrium.
Explain the Celsius Scale
A scale for measuring temperature that has units degrees Celsius and that is defined by the freezing point and boiling point of pure water at atmospheric pressure (1.01 x10^3Pa): 0 degrees and 100 degrees respectively.
Explain the absolute temperature scale
A scale for measuring temperature based on absolute zero and the triple point of pure water. Unit is Kelvin. To convert from Kelvin to degrees, the equation is k=degrees + 273
Explain the kinetic model
A model that describes all substances to be comprised of atoms, molecules, or ions that are arranged dependent on the phase of the substance.
Define a solid
Highly ordered, closely packed atoms or molecules with very strong electrostatic forces of attraction between atoms or molecules. Atoms or molecules can have small vibrations and therefore have a small amount of kinetic energy.
Define a liquid
No fixed shape, but atoms or molecules still closely packed. Atoms and molecules can flow past each other but there is still electrostatic forces acting between the atoms or molecules. Higher kinetic energy than a solid.
Define a gas
No fixed shape and atoms, molecules are far apart from each other. Negligible electrostatic forces, so therefore can ignore the fact atoms and molecules are free to move past each other unless they collide head-on. Gases have high speed and therefore have the highest kinetic energy.
Describe Brownian Motion
The continuous and random movement of particles suspended in a fluid visible under a microscope.
Define Internal Energy
Is the sum of the random distribution of kinetic and particle energies associated with the molecules in a system.
Define temperature
The average kinetic energy of particles in a system.
Define Absolute Zero
0K or -273.15 degrees, here there is minimum internal energy and zero kinetic energy.
Define define specific heat capacity
The amount of heat energy required to raise 1kg of a substance by 1 degree or 1 Kelvin.
Define specific latent heat
The amount of energy per unit mass to change the phase of a substance.
