Topic B.1 Thermal Energy Transfers Flashcards
Temperature
Measure of the average random Ek of the molecules in the object. Scalar quantoty
What does the kelvin scale measure?
Absolute temperature - at 0K, the molecules of a substance have stopped moving. It therefore cannot be a negative value.
Internal Energy
The total of the total intermolecular potential energy of the molecules and the total random kinetic energy.
What is the total intermolecular potential energy?
Energy due to the forces between molecules
If you heat a substance, what happens to the total intermolecular potential energy?
It increases it by moving them further apart
What are the two types of kinetic energy?
The translational (whole molecules moving in a certain direction) and the rotational (molecules rotating about an axis)
If two substances are the same temperature, how could you describe their internal energy?
They will be different due to their different masses (number of molecules) and molecular arrangements
Transfer of energy
Energy moves from hot to cold objects
If two objects are in thermal contact,
Transfer of energy will occur until thermal equilibrium is achieved.
What is the difference between internal and thermal energy?
Internal energy is energy objects have, thermal energy is when the energy is being transferred.
What determines the density of a substance?
Size and arrangement of the molecules
Specific Heat Capacity (c)
The amount of energy required to raise the temperature of the unit mass of a substance by 1K.
Why do substances have different specific heat capacities?
Because different substances have different molecular structures, forces between molecules and/or atoms and densities.
