Kinetic Particle Model and Heat Flow Flashcards
Particles in Solids, Liquids and Gases
Three states of matter: solid, liquid gas. The arrangements of these provide them their properties.
In solids, partlces remain locked in place excpet for slight vibration.
In liquids, the particles can move around but remain relatively close.
In gas, the particles can move around and can be quite spread out.
Kinetic particle model of matter
The kinetic particle model of matter says that all particles have energy, and that this energy depends on the temperature of the particle.
Particles in a solid move the least, so have the least energy, while particles in a gas move them most, so have the most energy.
Particles with more energy move faster, and thus have more kinetic energy.
Thermal energy and heat
Thermal energy is the energy associated with the temperature of an object. An object that is hotter has has more thermal energy and vice versa.
Heating is the process of passing thermal energy from a hotter object to a cooler object.
Temperature and average kinetic energy
Temperature is a value that can be measured. Average kinetic energy is a measure of how much thermal energy is present in a substance. Higher average kinetic energy means higher thermal energy and therefore you measure a higher temperature.
Temperature and average kinetic energy are not the same thing, but they are related.
Average kinetic energy -> a measure of the thermal heat in a substance
Internal energy
Internal energy is the total energy associated with the random motion of particles and interactions between particles within a system.
The change in internal energy is the change in the kinetic energy of the particles of a substance due to either heat (Q), work (W) or both. Joules for units.
Internal Energy Formula
CHANGE IN INTERNAL ENERGY = HEAT + WORK DONE
DELTA U = Q + W
- if heat is added, Q +ve
- if heat is removed, Q is =ve
- if work was done ON the system, W +ve (system is compressed)
- if work is done by a system W is -ve (system expands)
